Fart is an English language vulgarism most commonly used in reference to flatulence. The word "fart" is generally considered unsuitable in a formal environment by modern English speakers, and it may be considered vulgar or offensive in some situations. Fart can be used as a noun or a verb. The immediate roots are in the Middle English words ferten, feortan or farten; which is akin to the Old High German word ferzan. Cognates are found in old Norse, Slavic and also Greek and Sanskrit. The word "fart" has been incorporated into the colloquial and technical speech of a number of occupations, including computing.

Fart is sometimes used as a nonspecific derogatory epithet, often to refer to 'an irritating or foolish person', and potentially an elderly person, described as an 'old fart'. This may be taken as an insult when used in the second or third person, but can potentially be a term of endearment, or an example of self deprecatory humour when used in the first person. The phrase 'boring old fart' was popularised in the UK in the late 1970s by the New Musical Express while chronicling the rise of punk. It was used to describe hippies and establishment figures in the music industry, forces of inertia against the new music.