Definition - An abbreviated or contracted form of a word or phrase. (obsolete).

1. This word predates the synonym abbreviation, which eventually superseded it.

Example -
The word can't is an abbreviature of the phrase can not.

Etymology -
The term ultimately derives from the Latin brevis, short.

Oxford English Dictionary -
Its first citation is from circa 1630:
"From mistake of letters or abbreviatures by the transcribers."
Note: The first citation for abbreviation in this sense is from 1727.
(Jackson Creed viii. 27 Wks. VIII. 116)

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