Ain't

Ain't is a contraction for am not, is not, are not, has not, and have not in the common English language vernacular. In some dialects ain't is also used as a contraction of do not, does not, and did not. The development of ain't for the various forms of to be not, to have not, and to do not occurred independently, at different times. The usage of ain't for the forms of to be not was established by the mid-18th century, and for the forms of to have not by the early 19th century.

The usage of ain't is a perennial subject of controversy in English. Ain't is commonly used by many speakers in oral or informal settings, especially in certain regions and dialects. Its usage is often highly stigmatized, and it can be used by the general public as a marker of low socio-economic or regional status or education level. Its use is generally considered non-standard by dictionaries and style guides except when used for rhetorical effect.

Ain't has several antecedents in English, corresponding to the various forms of to be not and to have not that ain't contracts. The development of ain't for to be not and to have not is a diachronic coincidence; in other words, they were independent developments at different times.

Ain't as a contraction of am not is known from 1618. As the "mn" combination of two nasal consonants is disfavoured by many English speakers, the "m" of amn't began to be elided, reflected in writing with the new form an't.Aren't as a contraction for are not first appeared in 1675. In non-rhotic dialects, aren't lost its "r" sound, and began to be pronounced as an't.

An't (sometimes a'n't) arose from am not and are not almost simultaneously. An't first appears in print in the work of English Restoration playwrights. In 1695 an't was used as a contraction of "am not", in William Congreve's play Love for Love: "I can hear you farther off, I an't deaf". But as early as 1696 Sir John Vanbrugh uses an't to mean "are not" in The Relapse: "Hark thee shoemaker! These shoes an't ugly, but they don't fit me".

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