The definition of abbreviate is to use a shortened form of something, such as a word or phrase, to represent the full form.(verb)
To abbreviate the name of New York City, you would use NYC to represent the full city name.
See abbreviate in Webster's New World College Dictionary
See abbreviate in American Heritage Dictionary 4
transitive verb ab·bre·vi·at·ed, ab·bre·vi·at·ing, ab·bre·vi·ates
Origin: Middle English abbreviaten
Origin: , from Late Latin abbreviāre, abbreviāt-
Origin: : ad-, ad-
Origin: + breviāre, to shorten (from brevis, short; see mregh-u- in Indo-European roots).
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