ain't

Etymology
According to Etymology Online, the term was first attested in 1706 meaning, and it was used with that sense until the early 19th century, when it began to be used as a generic contraction for , , etc. in the Cockney dialect. It was then “popularized by representations of London cockney dialect in Dickens, etc., which led to the word being banished from correct English”.

The shift from to  parallels a similar change some dialects made to. In other dialects, the pronunciation shifted to, and the spelling , when used to mean “am not”, is due to the fact that both words are pronounced in some non-rhotic dialects. Historically, was present in many dialects of the English language, but not in the southeastern England dialect that became the standard, where it is only found in the construction.

As a contraction of and,  derives from the earlier form , which shifted from  to , and underwent h-dropping in most dialects.

Verb

 * 1)  Am not.
 * 2)  Are not, aren’t; is not, isn’t.
 * 3)  Have not, haven’t; has not, hasn’t, when used as an auxiliary.
 * 4)  Don’t, doesn’t.
 * 5)  Didn’t.
 * 1)  Have not, haven’t; has not, hasn’t, when used as an auxiliary.
 * 2)  Don’t, doesn’t.
 * 3)  Didn’t.
 * 1)  Have not, haven’t; has not, hasn’t, when used as an auxiliary.
 * 2)  Don’t, doesn’t.
 * 3)  Didn’t.
 * 1)  Don’t, doesn’t.
 * 2)  Didn’t.
 * 1)  Didn’t.
 * 1)  Didn’t.
 * 1)  Didn’t.
 * 1)  Didn’t.
 * 1)  Didn’t.

Derived terms

 * , if it ain't broken, don't fix it
 * , if it ain't broken, don't fix it

Translations

 * Swedish: e'nte