Ø
Encyclopedia
Ø — minuscule: "ø", is a vowel
and a letter
used in the Danish
, Faroese, Norwegian
and Southern Sami languages.
It's mostly used as a representation of mid front rounded vowels, such as ø
œ, except for Southern Sami where it's used as an [oe] diphtong.
The name of this letter is the same as the sound it represents (see usage). Though not its native name, among English-speaking typographers the symbol may be called a "slashed o" or "o with stroke". Although these names suggest it is a ligature
or a diacritic
al variant of the letter o, speakers of languages which use the letter ø hold that it is not. That is, emically
they perceive it as a different letter entirely. In Norwegian and Danish, it is alphabetized after "z" -- thus z æ ø and å.
In other languages that do not have the letter as part of the regular alphabet or in limited character sets such as ASCII
, ø is frequently replaced with the two-letter combination "oe".
Vowel
In phonetics, a vowel is a sound in spoken language, such as English ah! or oh! , pronounced with an open vocal tract so that there is no build-up of air pressure at any point above the glottis. This contrasts with consonants, such as English sh! , where there is a constriction or closure at some...
and a letter
Letter (alphabet)
A letter is a grapheme in an alphabetic system of writing, such as the Greek alphabet and its descendants. Letters compose phonemes and each phoneme represents a phone in the spoken form of the language....
used in the Danish
Danish and Norwegian alphabet
The Danish and Norwegian alphabet is based upon the Latin alphabet and has consisted of the following 29 letters since 1917 and 1955 , although Danish did not officially recognize the W as a separate letter until 1980....
, Faroese, Norwegian
Danish and Norwegian alphabet
The Danish and Norwegian alphabet is based upon the Latin alphabet and has consisted of the following 29 letters since 1917 and 1955 , although Danish did not officially recognize the W as a separate letter until 1980....
and Southern Sami languages.
It's mostly used as a representation of mid front rounded vowels, such as ø
Close-mid front rounded vowel
The close-mid front rounded vowel, or high-mid front rounded vowel, is a type of vowel sound, used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is , a lowercase letter o with a diagonal stroke through it, derived from the Danish, Norwegian...
œ, except for Southern Sami where it's used as an [oe] diphtong.
The name of this letter is the same as the sound it represents (see usage). Though not its native name, among English-speaking typographers the symbol may be called a "slashed o" or "o with stroke". Although these names suggest it is a ligature
Ligature (typography)
In writing and typography, a ligature occurs where two or more graphemes are joined as a single glyph. Ligatures usually replace consecutive characters sharing common components and are part of a more general class of glyphs called "contextual forms", where the specific shape of a letter depends on...
or a diacritic
Diacritic
A diacritic is a glyph added to a letter, or basic glyph. The term derives from the Greek διακριτικός . Diacritic is both an adjective and a noun, whereas diacritical is only an adjective. Some diacritical marks, such as the acute and grave are often called accents...
al variant of the letter o, speakers of languages which use the letter ø hold that it is not. That is, emically
Emic and etic
Emic and etic are terms used by anthropologists and by others in the social and behavioral sciences to refer to two kinds of data concerning human behavior...
they perceive it as a different letter entirely. In Norwegian and Danish, it is alphabetized after "z" -- thus z æ ø and å.
In other languages that do not have the letter as part of the regular alphabet or in limited character sets such as ASCII
ASCII
The American Standard Code for Information Interchange is a character-encoding scheme based on the ordering of the English alphabet. ASCII codes represent text in computers, communications equipment, and other devices that use text...
, ø is frequently replaced with the two-letter combination "oe".
Language usage
- In modern DanishDanish languageDanish is a North Germanic language spoken by around six million people, principally in the country of Denmark. It is also spoken by 50,000 Germans of Danish ethnicity in the northern parts of Schleswig-Holstein, Germany, where it holds the status of minority language...
, FaroeseFaroese languageFaroese , is an Insular Nordic language spoken by 48,000 people in the Faroe Islands and about 25,000 Faroese people in Denmark and elsewhere...
, and NorwegianNorwegian languageNorwegian is a North Germanic language spoken primarily in Norway, where it is the official language. Together with Swedish and Danish, Norwegian forms a continuum of more or less mutually intelligible local and regional variants .These Scandinavian languages together with the Faroese language...
, the letter is a monophthongMonophthongA monophthong is a pure vowel sound, one whose articulation at both beginning and end is relatively fixed, and which does not glide up or down towards a new position of articulation....
al close-mid front rounded vowelClose-mid front rounded vowelThe close-mid front rounded vowel, or high-mid front rounded vowel, is a type of vowel sound, used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is , a lowercase letter o with a diagonal stroke through it, derived from the Danish, Norwegian...
, the IPA symbolInternational Phonetic AlphabetThe International Phonetic Alphabet "The acronym 'IPA' strictly refers [...] to the 'International Phonetic Association'. But it is now such a common practice to use the acronym also to refer to the alphabet itself that resistance seems pedantic...
for which is also [ø]. To non-rhoticRhotic and non-rhotic accentsEnglish pronunciation can be divided into two main accent groups: a rhotic speaker pronounces a rhotic consonant in words like hard; a non-rhotic speaker does not...
English speakers, the vowel it most closely resembles aurally is the vowel in "bird" or "hurt". As with so many vowels, it has slight variations of "light" quality (in Danish, søster ("sister") is pronounced as ēū in French bleu) and "dark" quality (in Danish, "bønne" ("bean") is pronounced as the "ir" in the English word bird). The Danish and Norwegian alphabetDanish and Norwegian alphabetThe Danish and Norwegian alphabet is based upon the Latin alphabet and has consisted of the following 29 letters since 1917 and 1955 , although Danish did not officially recognize the W as a separate letter until 1980....
s contain a recording of a person reciting the Danish alphabet. In the SuðuroySuðuroySuðuroy is the southernmost of the Faroe Islands. The island covers 163.7 km². In 2010 there were 4763 inhabitants, but there has been a gradual decline in the population numbers ever since the 1950s....
-dialect of Faroese, the short ø is pronounced [ʏ], e.g. børn [bʏdn] (children). - The Southern Sami language uses the letter ø in Norway. It is used in the diphthongs yø [yo] and øø [oe]. In Sweden, the letter ö is preferred.
- Ǿ (Ø with an accent) may be used in DanishDanish languageDanish is a North Germanic language spoken by around six million people, principally in the country of Denmark. It is also spoken by 50,000 Germans of Danish ethnicity in the northern parts of Schleswig-Holstein, Germany, where it holds the status of minority language...
to distinguish its usage from a similar word with Ø. Example: "hunden gǿr" (Danish), "the dog barks" against "hunden gør (det)", "the dog does (it)". However, this only takes place in handwriting since Ǿ is not available in the Norwegian or Danish Windows keyboard layoutKeyboard layoutA keyboard layout is any specific mechanical, visual, or functional arrangement of the keys, legends, or key–meaning associations of a computer, typewriter, or other typographic keyboard....
. In DanishDanish languageDanish is a North Germanic language spoken by around six million people, principally in the country of Denmark. It is also spoken by 50,000 Germans of Danish ethnicity in the northern parts of Schleswig-Holstein, Germany, where it holds the status of minority language...
, "hunden gør", "the dog barks", may rather be replaced by the non-authorised spelling "hunden gøer" to distinguish it from "hunden gør (det)", "the dog does (it)". These idiosyncratic spellings are, however, not officially sanctioned. On Danish and Norwegian manual typewriters, ´ ("acute") may be typed above any letter. - Ø is used in the orthographies of several African languagesAfrican languagesThere are over 2100 and by some counts over 3000 languages spoken natively in Africa in several major language families:*Afro-Asiatic spread throughout the Middle East, North Africa, the Horn of Africa, and parts of the Sahel...
, such as LenduLenduThe Lendu, or Balendru, are an ethno-linguistic agriculturalist group residing in eastern Democratic Republic of Congo in the area west and northwest of Lake Albert, in particular the Ituri region of Orientale province. Their language is one of the most populous of the Central Sudanic languages...
, spoken in the Democratic Republic of the CongoDemocratic Republic of the CongoThe Democratic Republic of the Congo is a state located in Central Africa. It is the second largest country in Africa by area and the eleventh largest in the world...
, and Koonzime, spoken in CameroonCameroonCameroon, officially the Republic of Cameroon , is a country in west Central Africa. It is bordered by Nigeria to the west; Chad to the northeast; the Central African Republic to the east; and Equatorial Guinea, Gabon, and the Republic of the Congo to the south. Cameroon's coastline lies on the...
. - In Danish spelling, ø is also a word and means "island". The same word is spelled ö in Swedish and øy in Norwegian.
Similar letters
- The TurkishTurkish alphabetThe Turkish alphabet is a Latin alphabet used for writing the Turkish language, consisting of 29 letters, seven of which have been modified from their Latin originals for the phonetic requirements of the language. This alphabet represents modern Turkish pronunciation with a high degree of accuracy...
, AzerbaijaniAzerbaijani alphabetIn the Republic of Azerbaijan, the Azerbaijani alphabet refers to a Latin alphabet used for writing the Azerbaijani language. This superseded a previous versions based on Cyrillic and Arabic scripts....
, TurkmenTurkmen alphabetThe current official Turkmen alphabet as used in Turkmenistan is a Latin alphabet based on the Turkish alphabet, but with notable differences: J is used instead of the Turkish C; Ž is used instead of the Turkish J; Y is used instead of the dotless i ; Ý is used instead of the Turkish consonantal Y;...
, TatarTatar alphabetTwo scripts are currently used for the Tatar language: Cyrillic and Latin.-Introduction:While a Tatar version of the Latin alphabet called Jaŋalif had been in use during the 1930s, there is controversy in the matter of Latin-based Tatar alphabet for İdel-Ural Tatar. One dimension of the...
, FinnishFinnish alphabetThe Finnish alphabet is based on the Latin script, and especially the Swedish alphabet. Officially it comprises 28 letters:A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, X, Y, Z, Å, Ä, Ö...
, SwedishSwedish alphabetModern Swedish is written with a 29-letter Latin alphabet:Prior to the 13th edition of Svenska Akademiens ordlista in 2006, the letters and were collated together....
, IcelandicIcelandic alphabetThe modern Icelandic alphabet consists of the following 32 letters:It is a Latin alphabet with diacritics, in addition it includes the character eth Ðð and the runic letter thorn Þþ...
, Rotuman, GermanGerman alphabetThe modern German alphabet is an extended Latin alphabet consisting of 30 letters – the same letters that are found in the Basic modern Latin alphabet plus four extra letters.In German, the individual letters have neuter gender: das A, das B etc....
, EstonianEstonian alphabetThe Estonian alphabet is used for writing the Estonian language and is based on the Latin alphabet, with German influence. As such, the Estonian alphabet has the letters Ä, Ö, and Ü , which represent the vowel sounds , and , respectively...
, and Hungarian alphabetHungarian alphabetThe Hungarian alphabet is an extension of the Latin alphabet used for writing the Hungarian language.One sometimes speaks of the smaller and greater Hungarian alphabets, depending on whether or not the letters Q, W, X, Y are listed, which can only be found in foreign words and traditional...
s use the letter ÖÖ"Ö", or "ö", is a character used in several extended Latin alphabets, or the letter O with umlaut to denote the front vowels or . In languages without umlaut, the character is also used as a "O with diaeresis" to denote a syllable break, wherein its pronunciation remains an unmodified .- O-Umlaut...
instead of Ø. Hungarian uses Ő for the same sound lengthened. - Ø/ø is not related to, and should not be confused with, the similar-looking GreekGreek alphabetThe Greek alphabet is the script that has been used to write the Greek language since at least 730 BC . The alphabet in its classical and modern form consists of 24 letters ordered in sequence from alpha to omega...
Φ/φ or the Cyrillic Ф/ф. - The Cyrillic alphabetCyrillic alphabetThe Cyrillic script or azbuka is an alphabetic writing system developed in the First Bulgarian Empire during the 10th century AD at the Preslav Literary School...
has ӨOe (Cyrillic)Oe or Barred O is a letter of the Cyrillic alphabet.- Shape :Its form was copied from the Latin letter Barred O used in Jaŋalif and other alphabets. Despite having a similar shape, it is genetically related neither to the Greek letter Theta nor to the archaic Cyrillic letter Fita...
as the equivalent letter, which is used in the Cyrillic alphabets for KazakhKazakh alphabetThe Kazakh alphabets are the alphabets used to write the Kazakh language. The Kazakh language uses the following alphabets:* The Cyrillic script is officially used in the Republic of Kazakhstan and Bayan-Ölgiy Province in Mongolia...
, MongolianMongolian Cyrillic alphabetThe Mongolian Cyrillic script is the writing system used for the Khalkha dialect of the Mongolian language as the standard dialect of the modern state of Mongolia. Cyrillic has not been adopted by the Khalkha in the Inner Mongolia region of China, who still use the Mongolian script.Mongolian...
, AzerbaijaniAzerbaijani alphabetIn the Republic of Azerbaijan, the Azerbaijani alphabet refers to a Latin alphabet used for writing the Azerbaijani language. This superseded a previous versions based on Cyrillic and Arabic scripts....
, etc. - In linguistics, the capital is used to refer to the linguistic zeroZero (linguistics)A zero, in linguistics, is a constituent needed in an analysis but not realized in speech. This implies that there is a lack of an element where a theory would expect one. It is usually written with the symbol "", in Unicode .There are several kind of zeros....
. - The letter Ø-with-umlaut was used by the Øresund bridgeOresund BridgeThe Øresund or Öresund Bridge is a combined twin-track railway and dual carriageway bridge-tunnel across the Øresund strait.The bridge connects Sweden and Denmark, and it is the longest road and rail bridge in Europe. The Øresund Bridge also connects two major Metropolitan Areas: those of the...
company, as part of their logoLogoA logo is a graphic mark or emblem commonly used by commercial enterprises, organizations and even individuals to aid and promote instant public recognition...
type, to symbolize its union between Sweden and Denmark. Since it did not exist in computer fonts, it was not used in text. The logotype now uses the spelling Øresundsbron, with Øresunds- being Danish and -bron being Swedish. The letter Ø-with-umlaut sometimes appears on packaging meant for the Scandinavian market. For example liquorice brand Snøre/Snöre's logo on the packaging is Snø̈re.
History
There are at least two theories about the origin of the letter ø:- It possibly arose as a version of the ligatureLigature (typography)In writing and typography, a ligature occurs where two or more graphemes are joined as a single glyph. Ligatures usually replace consecutive characters sharing common components and are part of a more general class of glyphs called "contextual forms", where the specific shape of a letter depends on...
, ŒŒŒ œŒ is a Latin alphabet grapheme, a ligature of o and e. In medieval and early modern Latin, it was used to represent the Greek diphthong οι, a usage which continues in English and French...
, of the digraphDigraph (orthography)A digraph or digram is a pair of characters used to write one phoneme or a sequence of phonemes that does not correspond to the normal values of the two characters combined...
"oe", with the horizontal line of the "e" written across the "o". - That it arose in Anglo-Saxon England as an O and an I written in the same place, to represent a long close /ø/ sound resulting from i-mutationGermanic umlautIn linguistics, umlaut is a process whereby a vowel is pronounced more like a following vowel or semivowel. The term umlaut was originally coined and is used principally in connection with the study of the Germanic languages...
of /o/: compare BedeBedeBede , also referred to as Saint Bede or the Venerable Bede , was a monk at the Northumbrian monastery of Saint Peter at Monkwearmouth, today part of Sunderland, England, and of its companion monastery, Saint Paul's, in modern Jarrow , both in the Kingdom of Northumbria...
's NorthumbriaNorthumbriaNorthumbria was a medieval kingdom of the Angles, in what is now Northern England and South-East Scotland, becoming subsequently an earldom in a united Anglo-Saxon kingdom of England. The name reflects the approximate southern limit to the kingdom's territory, the Humber Estuary.Northumbria was...
n Anglo-Saxon period spelling Coinualch for standard Cēnwealh (a man's name) (in a text in LatinLatinLatin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
). Later the letter ø disappeared from Anglo-Saxon as the Anglo-Saxon sound /ø/ changed to /e/, but by then use of the letter ø had spread from England to ScandinaviaScandinaviaScandinavia is a cultural, historical and ethno-linguistic region in northern Europe that includes the three kingdoms of Denmark, Norway and Sweden, characterized by their common ethno-cultural heritage and language. Modern Norway and Sweden proper are situated on the Scandinavian Peninsula,...
.
Computers
- In Unicode the letters have the respective code points and . The code points are the same as in the older standard ISO 8859-1.
- In the TeXTeXTeX is a typesetting system designed and mostly written by Donald Knuth and released in 1978. Within the typesetting system, its name is formatted as ....
/LaTeXLaTeXLaTeX is a document markup language and document preparation system for the TeX typesetting program. Within the typesetting system, its name is styled as . The term LaTeX refers only to the language in which documents are written, not to the editor used to write those documents. In order to...
typesetting system, the letter is produced by \o - On a Mac operating system using a US English-language keyboard, the letter can be typed by holding the [Option] keyOption keyThe Option key is a modifier key present on Apple keyboards. It is located between the Control key and Command key on a typical Mac keyboard. There are two option keys on modern Mac desktop and notebook keyboards, one on each side of the space bar....
while typing O, or o, to yield Ø, or ø. - On an AmigaAmigaThe Amiga is a family of personal computers that was sold by Commodore in the 1980s and 1990s. The first model was launched in 1985 as a high-end home computer and became popular for its graphical, audio and multi-tasking abilities...
operating system using any keyboard map, the letter can be typed by holding the [Alt] keyAlt keyThe Alt key on a computer keyboard is used to change the function of other pressed keys. Thus, the Alt key is a modifier key, used in a similar fashion to the Shift key. For example, simply pressing "A" will type the letter a, but if you hold down either Alt key while pressing A, the computer...
while typing O, or o, to yield Ø, or ø. - On Microsoft WindowsMicrosoft WindowsMicrosoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
, using the "United States-International" keyboard setting, it can be typed by holding down the Alt-GrAltGr keyAltGr is a modifier key found on many computer keyboards and primarily used to type characters that are unusual for the locale of the keyboard layout, such as currency symbols and accented letters...
key and pressing "L". It can also be typed under any keyboard setting by holding down the [Alt] key while typing 0216 or 0248 on the numeric keypadNumeric keypadA numeric keypad, numpad or tenkey for short, is the small, palm-sized, seventeen key section of a computer keyboard, usually on the very far right. The numeric keypad features digits 0 to 9, addition , subtraction , multiplication and division symbols, a decimal point and Num Lock and Enter keys...
, provided the system uses code pageCode pageCode page is another term for character encoding. It consists of a table of values that describes the character set for a particular language. The term code page originated from IBM's EBCDIC-based mainframe systems, but many vendors use this term including Microsoft, SAP, and Oracle Corporation...
1252 as system default. (Code page 1252 is a superset of ISO 8859-1, and 216 and 248 are the decimal equivalents of hexadecimalHexadecimalIn mathematics and computer science, hexadecimal is a positional numeral system with a radix, or base, of 16. It uses sixteen distinct symbols, most often the symbols 0–9 to represent values zero to nine, and A, B, C, D, E, F to represent values ten to fifteen...
D8 and F8.) - Using Microsoft WordMicrosoft WordMicrosoft Word is a word processor designed by Microsoft. It was first released in 1983 under the name Multi-Tool Word for Xenix systems. Subsequent versions were later written for several other platforms including IBM PCs running DOS , the Apple Macintosh , the AT&T Unix PC , Atari ST , SCO UNIX,...
, ø and Ø may be typed by pressing CtrlControl keyIn computing, a Control key is a modifier key which, when pressed in conjunction with another key, will perform a special operation ; similar to the Shift key, the Control key rarely performs any function when pressed by itself...
-/ followed by either minuscule or majuscule O. - In HTML character entity references, needed in cases where the letter is not available by ordinary coding, the codes are Ø and ø.
- In the X Window SystemX Window SystemThe X window system is a computer software system and network protocol that provides a basis for graphical user interfaces and rich input device capability for networked computers...
environment, one can produce these characters by pressing Alt-Gr and o or O, or by pressing the Multi key followed with a slash and then o or O. - In some systems, such as older versions of MS-DOSMS-DOSMS-DOS is an operating system for x86-based personal computers. It was the most commonly used member of the DOS family of operating systems, and was the main operating system for IBM PC compatible personal computers during the 1980s to the mid 1990s, until it was gradually superseded by operating...
, the letter Ø is not part of the widely used code page 437Code page 437IBM PC or MS-DOS code page 437 is the character set of the original IBM PC. It is also known as CP 437, OEM 437, PC-8, MS-DOS Latin US or sometimes misleadingly referred to as the OEM font, High ASCII or Extended ASCII....
. In Scandinavian codepages, Ø replaces the yen sign (¥)¥¥ is a currency sign used by the Japanese yen and the Chinese yuan currencies. The symbol resembles a Latin letter Y with a double stroke. The base unit of both currencies shared the same Chinese character pronounced yuán in Mandarin Chinese and en in Standard Japanese...
at 165, and ø replaces the ¢Cent (currency)In many national currencies, the cent is a monetary unit that equals 1⁄100 of the basic monetary unit. Etymologically, the word cent derives from the Latin word "centum" meaning hundred. Cent also refers to a coin which is worth one cent....
sign at 162. - In Unicode, Ǿ and ǿ have the code points U+01FE and U+01FF. They are not available in the Microsoft Windows keyboard layout for Danish.
Symbol
- The symbol ø is used in the International Phonetic AlphabetInternational Phonetic AlphabetThe International Phonetic Alphabet "The acronym 'IPA' strictly refers [...] to the 'International Phonetic Association'. But it is now such a common practice to use the acronym also to refer to the alphabet itself that resistance seems pedantic...
to indicate the sound of the Danish and Norwegian letter, the close-mid front rounded vowelClose-mid front rounded vowelThe close-mid front rounded vowel, or high-mid front rounded vowel, is a type of vowel sound, used in some spoken languages. The symbol in the International Phonetic Alphabet that represents this sound is , a lowercase letter o with a diagonal stroke through it, derived from the Danish, Norwegian...
. - In music theory, ø is widely used as a chord label to represent a half-diminished chord. (m7b5: 1 - b3 - b5 - b7). For example, Cm7b5 would be notated as Cø.
- The letter ∅ with two brackets symbolizing a double null setNull setIn mathematics, a null set is a set that is negligible in some sense. For different applications, the meaning of "negligible" varies. In measure theory, any set of measure 0 is called a null set...
was used as the gang symbol for the Lords of ChaosLords of Chaos (self-styled teen militia)The Lords of Chaos was a self-styled teen militia formed on April 13, 1996, in Fort Myers, Florida. They gained notoriety for a crime spree that ended with the April 30, 1996, murder of one of the boys' teachers, Mark Schwebes, who served as Riverdale High School's band director.The Lords of...
, a self-styled teen militia. Ex. ( Ø ) - In linguistics, a zero element (i.e. a grammatical element represented by the absence of a word) is represented by ∅, such as the difference in English between the articles "the", "a", "an", and instances where nouns are not preceded by articles, represented by ∅.
- In phpMyAdminPhpMyAdminphpMyAdmin is an open source tool written in PHP intended to handle the administration of MySQL with the use of a Web browser. It can perform various tasks such as creating, modifying or deleting databases, tables, fields or rows; executing SQL statements; or managing users and...
, the ø is used to substitute the "mean" or "average" - In audio engineering, the ø is used to represent a signal whose polarity (sometimes called phase) has been reversed.
- Many scholars in biological and human sciences use Mø as shorthand notation for "macrophage".
- The American Post-Hardcore band UnderoathUnderoathUnderoath is an American Christian metalcore band from Tampa, Florida. Founded by Dallas Taylor and Luke Morton on November 30, 1997 in Ocala, Florida, subsequently its additional members were from Tampa, Florida...
uses the Ø symbol in their logo and for the cover of the "Ø (Disambiguation)Ø (Disambiguation)Ø is the seventh album by American metalcore band Underoath. Released on November 9, 2010 through Tooth & Nail Records, the album is the band's first without founding member Aaron Gillespie, the first with Daniel Davison, formerly of Norma Jean. As of this album, none of the members that appeared...
" album. (according to the Metal umlaut tradition).
Similar symbols
- The letter "Ø" is sometimes used in mathematics as a replacement for the symbol "∅" (Unicode character U+2205), referring to the empty setEmpty setIn mathematics, and more specifically set theory, the empty set is the unique set having no elements; its size or cardinality is zero. Some axiomatic set theories assure that the empty set exists by including an axiom of empty set; in other theories, its existence can be deduced...
as established by BourbakiNicolas BourbakiNicolas Bourbaki is the collective pseudonym under which a group of 20th-century mathematicians wrote a series of books presenting an exposition of modern advanced mathematics, beginning in 1935. With the goal of founding all of mathematics on set theory, the group strove for rigour and generality...
. The "∅" symbol is always drawn as a slashed circleCircleA circle is a simple shape of Euclidean geometry consisting of those points in a plane that are a given distance from a given point, the centre. The distance between any of the points and the centre is called the radius....
, whereas in most typefaces the letter "Ø" is a slashed ellipseEllipseIn geometry, an ellipse is a plane curve that results from the intersection of a cone by a plane in a way that produces a closed curve. Circles are special cases of ellipses, obtained when the cutting plane is orthogonal to the cone's axis...
. - The diameterDiameterIn geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints are on the circle. The diameters are the longest chords of the circle...
symbol (⌀) (Unicode character U+2300) is similar to the letter Ø, and in some typefaceTypefaceIn typography, a typeface is the artistic representation or interpretation of characters; it is the way the type looks. Each type is designed and there are thousands of different typefaces in existence, with new ones being developed constantly....
s it even uses the same glyphGlyphA glyph is an element of writing: an individual mark on a written medium that contributes to the meaning of what is written. A glyph is made up of one or more graphemes....
, although in many others the glyphs are subtly distinguishable. The diameter symbol is used extensively in engineering drawingEngineering drawingAn engineering drawing, a type of technical drawing, is used to fully and clearly define requirements for engineered items.Engineering drawing produces engineering drawings . More than just the drawing of pictures, it is also a language—a graphical language that communicates ideas and information...
s, and it is also seen anywhere that abbreviating "diameter" is useful, such as on camera lenses. For example, a lens with a diameter of 82 mm would be labeled ⌀ 82 mm. - Slashed zeroSlashed zeroThe slashed zero is a representation of the number '0' , with a slash through it. In character encoding terms, it is an alternate glyph for the self-same zero character...
is an alternate glyphGlyphA glyph is an element of writing: an individual mark on a written medium that contributes to the meaning of what is written. A glyph is made up of one or more graphemes....
for the zero0 (number)0 is both a numberand the numerical digit used to represent that number in numerals.It fulfills a central role in mathematics as the additive identity of the integers, real numbers, and many other algebraic structures. As a digit, 0 is used as a placeholder in place value systems...
character. Its slash does not extend outside the ellipse (except in hasty handwriting). It is often used to distinguish "zero" ("0") from the Latin script letter "O" anywhere that people wish to preempt confounding of the two, particularly in encoding systemsCodeA code is a rule for converting a piece of information into another form or representation , not necessarily of the same type....
, scientific and engineering applications, computer programmingComputer programmingComputer programming is the process of designing, writing, testing, debugging, and maintaining the source code of computer programs. This source code is written in one or more programming languages. The purpose of programming is to create a program that performs specific operations or exhibits a...
(such as software developmentSoftware developmentSoftware development is the development of a software product...
), and telecommunications.