mid-15c., "to make shorter," from Latin abbreviatus, past participle of abbreviare "to shorten, make brief," from ad "to" (see ad-) + breviare "shorten," from brevis "short, low, little, shallow" (from PIE root *mregh-u- "short").
Specifically of words by 1580s. Also sometimes 15c. abbrevy, from French abrevier (14c.), from Latin abbreviare. Related: Abbreviated; abbreviating.
early 15c., abbreviacioun, "shortness; act of shortening; a shortened thing," from Old French abréviation (15c.) and directly from Late Latin abbreviationem (nominative abbreviatio), noun of action from past-participle stem of abbreviare "shorten, make brief," from Latin ad "to" (see ad-) + breviare "shorten," from brevis "short, low, little, shallow" (from PIE root *mregh-u- "short").
From 1580s specifically of words. Technically a part of a word, usually the initial letter or syllable, used for the whole word but with no indication of the rest of the word (as abbr. for abbreviation or abbreviate). A contraction is made by elision of certain letters or syllables from the body of a word but still indicates its full form (as fwd. for forward; rec'd. for received).
also a-b-c, late 13c. (spelled abece) from the first three letters of it taken as a word (compare alphabet, abecedary, Old French abecé, abecedé "alphabet," 13c.). The sense of "rudiments or fundamentals (of a subject)" is from late 14c. As a shortening of American Broadcasting Company from 1944 (in a Billboard magazine headline), earlier of Australian Broadcasting Corporation (1931). Related: ABCs.
by 1650s, "of or pertaining to Abdera," in Thrace, whose citizens were proverbial as provincials who would laugh at anything or anyone they didn't understand (Abderian laughter), making their town the Hellenic equivalent of Gotham (q.v.). Especially (or alternatively) as it was the birthplace of Democritus the atomist, the "Laughing Philosopher" (born c. 460 B.C.E.) who observed human follies.
1540s, "to disown, disinherit (children)," from Latin abdicatus, past participle of abdicare "to disown, disavow, reject" (specifically abdicare magistratu "renounce office"), literally "proclaim as not belonging to one," from ab "off, away from" (see ab-) + dicare "proclaim" (from PIE root *deik- "to show," also "pronounce solemnly," and see diction). Meaning "divest oneself of office, privilege, etc., before the term expires" is recorded by 1610s in English (it was in classical Latin). Related: Abdicated; abdicating.