Drill instructor A drill instructor is a non-commissioned officer in the armed forces with specific duties that vary by country. In the Military of the United States, they are assigned the duty of initiating new recruits entering the military into the customs and practices of military life.
	Drilling mud Drilling mud, also called drilling fluid, is a lubricant used while drilling oil well and natural gas wells and in exploration drilling rigs.
	Drilling rig A drilling rig is a structure housing equipment used to drill for ground water, oil, natural gas from underground reservoirs or to obtain mineral core samples. The term can refer to a land-based rig, a marine-based structure commonly called an 'offshore rig' or a structure that drills oil wells called an 'oil rig'.
	Drink The word drink is primarily a verb, meaning to ingest liquids. As a noun, it refers to the liquid thus ingested. It is often used in a narrower sense to refer to alcoholic beverages . Drink is also slang for a body of water, such as an ocean or a water hazard on a golf course .
	Drinking Drinking is the act of consuming a liquid through the mouth. Water is required for many of life's physiological processes, and excess or decreased water intake is associated with health problems. "Drinking" may refer specifically to the ingestion of alcohol depending on the context in which the term is used.
	Drinking straw The drinking straw is a device used for sucking up a liquid - usually a drink. A thin tube of plastic or other material, straight or with an accordion-like living hinge, it is employed by being held with one end in the mouth and another end in the drink. Muscle action reduces atmospheric pressure in the mouth, whereupon atmospheric pressure forces the drink up the straw.
	Drinking water Drinking water is water that is intended to be drinking by humans. Water of sufficient quality to serve as drinking water is called potable water whether it is used as such or not. Although many fresh water sources are drinkable by humans, they can be a disease Vector or cause long-term health problems if they do not meet certain water quality guidelines.
	Driver Driver may refer to a: * person driving * person Vehicular cycling * person railroad engineer * chauffeur * Golf club , usually used for the first shot on a par 4 or 5 hole
	Driver's license A driver's license, driver license, operator's license , driving licence , driver licence or driver's permit , is an official document which states that a person has the necessary qualifications to driving a motorized vehicle, such as a motorcycle, automobile, truck, or a bus.
	Driveshaft A driveshaft, driving shaft, or Cardan shaft is a machine for transmission power from the engine or motor to the point where useful Mechanical work is applied. Most engines or motors deliver power as torque through rotary motion: this is extracted from the linear motion of pistons in a reciprocating engine; water driving a water wheel; or forced air or water in a turbine.
	Driveway A driveway is a type of private road for local access to one or a small group of structures, and is owned and maintained by an individual or group. Driveways do not usually have traffic lights. However, at a few driveways to commercial buinesses and parks in which there is more traffic than a "Private Drive", there is an exception.
	Driving Driving is the controlled operation of a vehicle, which is usually a motor vehicle such as a truck, bus, or automobile. Although direct operation of a bicycle, a mounted animal or — at least in the United Kingdom, the United States and Canada — a motorcycle is commonly called riding, such operators usually considered to be drivers by law since they are required to obey those rules of the road which apply to all drivers.
	Driving range A driving range is an area where golfers can practice their swing. They are typically run by businesses or sometimes by universities . Distances are usually marked by target putting green at regular distances. Golfers pay for large bucket of balls and hit at their leisure. Often there are golf professionals available to give lessons and instruction.
	Driving wheel On a steam locomotive, a driving wheel is a powered wheel which is driven by the locomotive's pistons. On a conventional, non-articulated locomotive, the driving wheels are all coupled together with side rods; normally one pair is directly driven by the main rod which is connected to the end of the piston rod; power is transmitted to the others through the side rods.
	Drogheda Drogheda or [dr?h?d?]) is an industrial and port town in County Louth on the east coast of Ireland, 56 km north of Dublin. The town is increasingly populated by commuters working in Dublin. In 2006 the population stood at 28,894. In recent years Drogheda has been shedding its industrial image, as an increasing number of people employed in the retail, services and technology sectors have been looking to the local economy instead of Dublin for employment.
	Drogue parachute A drogue parachute is a type of parachute designed to be deployed from a rapidly moving object. It is often used to gain control of very fast descents, including those of spacecraft during reentry. A drogue parachute is more enlongated and far thinner than a conventional parachute, and thus provides less drag.
	Dromaeosauridae Dromaeosaurids, 'raptors' or members of the family Dromaeosauridae are theropod dinosaurs. They were mainly small, gracile carnivores that flourished in the Cretaceous Period. In popular usage they are often called "raptors" after the Velociraptor and their similarities to modern carnivorous bird of prey, which are also commonly called raptors.
	Dromaius Dromaius is a genera of Ratite present in Australia. There is one extant species, Dromaius novaehollandiae commonly known as the Emu. In his original 1816 description of the emu, Louis Jean Pierre Vieillot used two genus names; first Dromiceius, then Dromaius a few pages later.
	Dromedary The Dromedary Camel is a large even-toed ungulate native to northern Africa and western Asia, and is the best-known member of the camel family. The dromedary camel has one hump on its back, in contrast to the Bactrian Camel which has two. The dromedary is sometimes called an Arabian Camel.
	Drooping Brome Drooping brome, is a Poaceae native to Europe, southwestern Asia and northern Africa. It is an Annual plant, usually germinating in the autumn, overwintering as a seedling, then flowering in the spring or early summer. If winter rainfall is limiting and spring moisture is adequate, the seeds will germinate in the spring, and the plants will flower that summer.
	Drop zone In parachuting, a Drop zone is the area above and around a location where a skydiver or parachutist freefalls and expects to land. In many cases skydivers refer to the airfield at which they board aircraft in order to jump the Dropzone or DZ, but the term dropzone is intended to refer to the area in which freefall skydiving and parachute descents take place.
	Dropkick A dropkick is an Professional wrestling attacks in professional wrestling. It is defined as an attack where the wrestler jumps up and kicks the opponent with the soles of both feet, this sees the wrestler twist as they jump so that when the feet connect with the opponent one foot is raised higher that the other and the wrestler falls back to the mat on their side, or front.
	Dropped Dropped is the fifth full-length album by Industrial music/Hip hop music artists Consolidated, which was released in 1998. The title is a reaction to having been "dropped" by London Records because of poor album sales.
	Droseraceae Droseraceae is the botanical name for a family of flowering plants. The family is also known under its common name, the sundew family. It consists of carnivorous plants: besides the sundews, the genus Drosera, it also contains the even more famous Venus fly trap, Dionaea muscipula.
	Drosophila Drosophila is a genus of small fly whose members are often called small Drosophilidae, or more appropriately vinegar flies, wine flies, pomace flies, grape flies, and picked fruit-flies. A second insect family, the Tephritidae are also called fruit flies; they feed on unripe or ripe fruit.
	Drosophila melanogaster Drosophila melanogaster is a two-winged insect that belongs to the Diptera, the Order of the Fly. The species is commonly known as the Drosophilidae, and is one of the most commonly used model organisms in biology, including studies in genetics, physiology and Life-history theory.
	Drosophilidae Drosophilidae is a diverse, cosmopolitan family of flies, including the genus Drosophila, which includes fruit flies, vinegar fly, wine flies, pomace flies, grape flies, and picked fruit-flies. The best known species is Drosophila melanogaster that is used extensively for studies concerning genetics, development, physiology, ecology, behaviour, etc.
	Drosophyllum Drosophyllum is a genus of carnivorous plants containing the single species Drosophyllum lusitanicum. In appearance, it is similar to the related genus Drosera, and to the much more distantly related Byblis. Drosophyllum lusitanicum is native to Portugal, Spain and Morocco, and is one of the few carnivorous plants to grow in dry, alkaline soil.
	Drought A drought is an abnormally dry period when there is not enough water to support agricultural, urban or environmental water needs. A drought usually refers to an extended period of below-normal rainfall, but can also be caused by drying bores or lakes, or anything that reduces the amount of water available.
	Drug A drug is a substance, such as a pharmaceutical product, used in or on the surface of the body to diagnose, cure, mitigate, treat, or prevent disease, or to otherwise affect the structure or function of the body. It is usually synthesized outside of an organism, but introduced into an organism to produce its action.
	Drug abuse Drug abuse has a wide range of definitions, all of them relating either to the misuse or overuse of a psychoactive drug or performance enhancing drug for a non-therapeutic or non-medical effect, or referring to any use of illegal drug in the absence of a required, yet practically impossible to get, license from a government authority, in the USA this is the DEA.
	Drug Enforcement Administration The Drug Enforcement Administration is a United States Department of Justice law enforcement agency, a federal police service tasked with enforcing the Controlled Substances Act of 1970. Not only is the DEA the lead agency for domestic enforcement of federal drug laws, it also has sole responsibility for coordinating and pursuing U.S.
	Drugstore Drugstore is a common term for a pharmacy. Drugstore could also refer to: * Drugstore, a United Kingdom-based pop rock trio. * Drugstore, the 1995 debut album recorded by the band Drugstore .
	Druid In Celtic polytheism the word druid denotes the priestly class in ancient Celts societies, which existed through much of Western Europe north of the Alps and in the British Isles until they were supplanted by Roman government and, later, Christianity. Druidic practices were part of the culture of all the tribal peoples called "Keltoi" and "Galatia" by Greeks and "Celtae" and "Gauls" by Romans, which evolved into modern English "Celtic" and "Gaulish language".
	Drum A drum is a musical instrument in the Percussion instrument family, technically classified as a membranophone. Drums consist of at least one Skin, called a drumhead or drumskin, that is stretched over a shell and struck, either directly with parts of a player's body, or with some sort of implement such as a drumstick, to produce sound.
	Drum brake A drum brake is a brake in which the friction is caused by a set of shoes or pads that press against the inner surface of a rotating drum. The drum is connected to a rotating wheel.
	Drum Major The term drum major describes several similar appointments in marching bands, drum and bugle corps, and pipe bands. In common to all these forms of marching arts is that the drum major is responsible for providing commands to the ensemble regarding where to march, what to play, and what tempo.
	Drumlin A drumlin is an elongated whale-shaped hill formed by glacier action. Its long axis is parallel with the movement of the ice, with the blunter end facing into the glacial movement. Drumlins may be more than 150 ft high and more than miles long, and are often in drumlin fields of similarly shaped, sized and oriented hills.
	Drunkenness Drunkenness, in its most common usage, is the state of being intoxicated by consumption of ethanol to a degree that mental and physical facilities are noticeably impaired. Common symptoms may include slurred speech, impaired balance, poor coordination, flushed face, reddened eyes and uncharacteristic behavior.
	Drupe In botany, a drupe is a type of fruit in which an outer fleshy part surrounds a shell of hardened endocarp with a seed inside. These fruits develop from a single carpel, and mostly from flowers with superior ovary. The definitive characteristic of a drupe is that the hard, lignified stone derives from the ovary wall of the flower.
	Druze The Druze are a distinct religious community based mostly in the Middle East who are an offshoot of Islam and influenced by other religions and philosophies, including Greek philosophy. The Druze consider themselves politically as "an Islamic Unist, reformatory sect", although they are not considered Muslims by most Muslims in the region.
	Dry Cell Dry Cell was a four-piece nu metal/hard rock music group originating from California in the United States. The band broke up late 2005, after vocalist Jeff Gutt and guitarist Danny Hartwell departed.
	Dry dock A dry dock is a narrow basin or vessel that can be flooded to allow a load to be floated in, then drained to allow that load to come to rest on a dry platform.
	Dry run A Dry Run is a testing process where the effects of a possible failure are intentionally mitigated. For example, an aerospace company may conduct a 'dry run' of a takeoff using a new aircraft on a runway before the first test flight. In computer studies, a dry run is a mental run of a program, where the programmer examines the source code one step at a time and determines what it will do when run.
	Dryad Dryads are female Tree spirits in Greek mythology. In Greek drys signifies 'oak,' from an Indo-European root *derew(o)- 'tree' or 'wood.' Thus dryads are specifically the nymphs of oak trees, though the term has come to be used for all tree nymphs in general. "Such deities are very much overshadowed by the divine figures defined through poetry and cult," Walter Burkert remarked of Greek nature deities.
	DRYAD The DRYAD Numeral Cipher/Authentication System is a simple, paper cryptographic system currently in use by the United States military for authentication and for encryption of short, numerical messages. Every unit with a radio is given a set of DRYAD code sheets. A single sheet is valid for a limited time, called a cryptoperiod.
	Dryadella Dryadella is a genus of miniature orchids, reaching from 3 to 6 cm. There are about 40 species, distributed from southern Mexico to southern Brazil and northern Argentina.
	Dryas octopetala Dryas octopetala is an arctic-alpine flowering plant in the family Rosaceae. It is a small prostrate evergreen subshrub forming large colonies, and is a popular flower in rock gardens. The specific epithet octopetala derives from the Greek language octo and petalon, referring to the eight petals of the flower, an unusual number in the Rosaceae, where five is the normal number.
	Drymarchon The genus Drymarchon of colubrid snakes includes the Indigo snakes and various other relatives, including the Cribo snakes, all of which are found in the Southeastern United States, Central America, and South America. Species in this genus include: * Newly discovered species Drymarchon caudomaculatus
	Dryopithecus Dryopithecus was a genus of apes that lived in Eastern Africa during the Upper Miocene period, from 12 to 9 million years ago, and which could have been the evolutionary ancestor of modern man. After evolving near the southern end of the African Rift Valley, it expanded throughout the African continent and got as far as Asia and Europe.
	Dryopteridaceae The Dryopteridaceae includes many ferns prized as ornamental plants, including the Dryopteriss, Holly ferns, Florist's fern, and others. All of the fronds of Dryopteridaceae ferns contain round Sorus on the underside of the pinnae unlike some other ferns which have separate specialized reproductive fronds.
	Dryopteris Dryopteris is a genus of about 250 species of ferns with distribution in the temperate Northern Hemisphere, with the highest species diversity in eastern Asia. Many of the species have stout, slowly creeping rootstocks that form a crown, with a vase-like ring of fronds.
	Dryopteris filix-mas Dryopteris filix-mas is one of the commonest ferns of the temperate Northern Hemisphere, occurring throughout much of Europe, Asia and North America. It favours damp shaded areas and is particularly ubiquitous in the understory of woodlands, but also found in shady places on hedge-banks, rocks and screes.
	Drywall Drywall or Plasterboard is a common material used globally for the construction of interior walls and ceilings.
	Dual carriageway A dual carriageway or divided highway is a road or highway in which the two directions of traffic are separated by a central barrier or strip of land, known as a central reservation or median.
	Dualism The term dualism has a number of uses in the history of thinking. In a given domain of knowledge, the idea involves the existence of two fundamental classes of things, or principles, often in opposition to each other. In theology, dualism can refer to the belief that there are two basic opposing principles, such as Goodness and value theory, and evil.
	Dubai Dubai refers to either: * one of the seven emirates that make up the United Arab Emirates on the Persian Gulf, or * that emirate's main city, sometimes called "Dubai City" to distinguish it from the emirate. Dubai is the most populous and second largest emirate of the United Arab Emirates after Abu Dhabi.
	Dubbin Dubbin is a wax product used to soften, condition and waterproof leather. It consists of natural wax, oil and tallow. It is different from shoe polish, which is used to impart shine and colour to leather. Dubbin has been used since medieval times. The name 'dubbin' is a contraction of the gerund "dubbing", describing the action of applying the wax to leather.
	Dublin Dublin is the capital and the largest city of the Republic of Ireland , located near the midpoint of Ireland's east coast, at the mouth of the River Liffey and at the centre of the County Dublin. Originally founded as a centre for the Viking slave trade, the city has been Ireland's capital city since Middle Ages times.
	Dubliners Dubliners is a collection of short stories by James Joyce, published in 1914. The fifteen stories were meant to be a frank and satirical depiction of the Ireland middle classes living in and around Dublin in the early years of the 20th century. Joyce, who would later be acknowledged as the pioneer of stream of consciousness writing, here uses a more superficially realism style to give a crisp, yet intriguing description of characters.
	Dubrovnik Dubrovnik | colspan="2" style="text-align: center;" | [Image:Ragusa.png|thumb|right|Republic of Ragusa before 1808]] Dubrovnik is an old city on the Adriatic Sea coast in the extreme south of Croatia, positioned at at the terminal end of the Isthmus of Dubrovnik.
	Ducat The ducat is a gold coin that was used as a trade currency throughout Europe before World War I. Its weight is 3.494 grams which is 0.1125 troy ounce and of .986 pure gold, having a metal value of about Euro 43.82 as of October 2005. However, the value of gold is currently fluctuating; the value of one modern ducat is around 59EUR, $75USD, 41GBP, or 913EEK as of mid-July 2006.
	Duck Duck is the common name for a number of species in the Anatidae family of birds. The ducks are divided between several subfamilies listed in full in the Anatidae article. Ducks are mostly aquatic birds, mostly smaller than their relatives the swans and goose, and may be found in both fresh water and sea water.
	Duck Soup Duck Soup is a 1933 in film Marx Brothers' anarchic comedy film written by Bert Kalmar, Harry Ruby, Arthur Sheekman, and Nat Perrin and directed by Leo McCarey. It starred what were then billed as the "Four Marx Brothers" and also featured Margaret Dumont, Raquel Torres, and Louis Calhern.
	Duct tape Duct tape, originally known as duck tape, is a strong, fabric-based, multi-purpose adhesive tape, usually silver or black in color, although many other colors, including #Color Variants, have recently become available. Duct tape is usually 1.88 inches wide. It was originally developed during World War II in 1942 under the name "Duck Tape" as a waterproof sealing tape for ammunition cases.
	Dudley Moore Dudley Stuart John Moore, Order of the British Empire , was a United Kingdom musician, actor and comedian who was enormously popular in his home country for many years but relatively unknown in the United States until he made the film 10 with Bo Derek.
	Due South Due South is an award-winning Canada television police drama created by Paul Haggis and produced by Alliance Communications, first airing in 1994. It followed the adventures of a fictional Royal Canadian Mounted Police Benton Fraser and his wolf companion Diefenbaker, living and working in Chicago.
	Duel A duel is a formalized type of combat in which two individuals participate. They usually develop out of a desire for one party to redress a perceived insult to his honor by the other participant in the duel. The goal of the duel is not so much to kill the opponent, as to restore one's own honor by being willing to risk one's life.
	Duffel Duffel is a municipality in the Belgium province of Antwerp. The municipality only comprises the town of Duffel proper. On January 1 2006 Duffel had a total population of 16,019. The total area is 22.71 square kilometre which gives a population density of 705 inhabitants per km.
	Dugald Stewart Dugald Stewart, Scotland philosopher, was born in Edinburgh. His father, Matthew Stewart, was professor of mathematics in the University of Edinburgh.