Git is mild profanity

Profanity

Profanity is a show of disrespect, or a desecration or debasement of someone or something. Profanity can take the form of words, expressions, gestures, or other social behaviors that are socially constructed or interpreted as insulting, rude, vulgar, obscene, desecrating, or other forms.The...

 with origins in British English

British English

British English, or English , is the broad term used to distinguish the forms of the English language used in the United Kingdom from forms used elsewhere...

 for a silly, incompetent, stupid, annoying, senile elderly or childish person.
It is usually an insult, more severe than twit or idiot

Idiot

An idiot, dolt, or dullard is a mentally deficient person, or someone who acts in a self-defeating or significantly counterproductive way. Archaically the word mome has also been used. The similar terms moron, imbecile, and cretin have all gained specialized meanings in modern times. An idiot is...

but less severe than wanker

Wanker

Wanker is a pejorative term of English origin, common in Commonwealth and ex-Commonwealth countries, including Britain, Ireland, Australia, New Zealand, and South Africa. It initially referred to an onanist but has since become a general insult. It is synonymous with tosser.-Meaning:The term wanker...

, arsehole

Asshole

The word asshole, a variant of arsehole, which is still prevalent in British and Australian English, is a term used pejoratively to describe the anus.-History:...

 or twat

Twat

The word twat has various functions. It is a vulgar synonym for the human vulva, but is more widely used as a derogatory epithet, especially in British English...

.

The word git first appeared in print in 1946, but is undoubtedly older. It is originally an alteration of the word get, dating back to the 14th century. A shortening of beget, get insinuates that the recipient is someone's misbegotten offspring and therefore a bastard. In parts of northern England, Northern Ireland

Northern Ireland

Northern Ireland is one of the four countries of the United Kingdom. Situated in the north-east of the island of Ireland, it shares a border with the Republic of Ireland to the south and west...

 and Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

 get is still used in preference to git.

The word has been ruled by the Speaker of the House of Commons to be unparliamentary language

Unparliamentary language

In a Westminster system, unparliamentary language is words or phrases that are deemed to be inappropriate for use in the House whilst it is in session. This includes, but is not limited to the suggestion of dishonesty or profanity. The most prohibited case is any suggestion that another member is...

.

The word was used self-deprecatingly by Linus Torvalds

Linus Torvalds

Linus Benedict Torvalds is a Finnish software engineer and hacker, best known for having initiated the development of the open source Linux kernel. He later became the chief architect of the Linux kernel, and now acts as the project's coordinator...

 in naming the git source control package

Git (software)

Git is a distributed revision control system with an emphasis on speed. Git was initially designed and developed by Linus Torvalds for Linux kernel development. Every Git working directory is a full-fledged repository with complete history and full revision tracking capabilities, not dependent on...

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