"having sufficient power or means," early 14c., from Old French (h)able "capable; fitting, suitable; agile, nimble" (14c.), from Latin habilem, habilis "easily handled, apt," verbal adjective from habere "to hold" (from PIE root *ghabh- "to give or receive").

"Easy to be held," hence "fit for a purpose." The silent h- was dropped in English and resisted academic attempts to restore it 16c.-17c. (see H), but some derivatives (such as habiliment, habilitate) acquired it via French. Able seaman, one able to do any sort of work required on a ship, may be the origin of this:

Able-whackets - A popular sea-game with cards, in which the loser is beaten over the palms of the hands with a handkerchief tightly twisted like a rope. Very popular with horny-fisted sailors. [Smyth, "Sailor's Word-Book," 1867]

early 14c., abominacioun, "abominable thing or action;" late 14c., "feeling of disgust, hatred, loathing," from Old French abominacion "abomination, horror, repugnance, disgust" (13c.) and directly from Latin abominationem (nominative abominatio) "abomination," noun of action from past-participle stem of abominari "shun as an ill omen," from ab "off, away from" (see ab-) + omin-, stem of omen (see omen).

In biblical use, often "that which is ceremonially impure." The meaning was intensified by folk etymology derivation from Latin ab homine "away from man" (thus "beastly"); Wycliffe and Chaucer both have abhominacioun, and abhominable was mocked by Shakespeare in "Love's Labour's Lost." The U.S. Tariff of Abominations, with high protective duties offensive to the South, was passed in 1828.

"be in great plenty," early 14c., from Old French abonder "to abound, be abundant, come together in great numbers" (12c.), from Latin abundare "overflow, run over," from Latin ab "off, away from" (see ab-) + undare "rise in a wave," from unda "a wave" (from PIE *unda-, nasalized form of root *wed- (1) "water; wet"). Related: Abounded; abounding; abounder "one who has plenty or is wealthy" (1755).

English seems to always have used in the -ou- spelling, though in Middle English an unetymological h- sometimes was added. The vowel in Old French abonder, abondance is a continuation of a Merovingian Latin scribal use of -o- for classical Latin -u- to attempt to identify a sound that had evolved since classical times. In French eventually this sound came to be represented by -ou-. Compare French tour "tower," from Old French tor, from Latin turris; court (n.), from Old French cort, from Latin curtus; French outre from Latin ultra, etc. However -o- remained before a nasal (as nombre from numerus, monde from mundum, etc.).

early 14c., "an attack of fever," from Old French acces "onslaught, attack; onset (of an illness)," from Latin accessus "a coming to, an approach; way of approach, entrance," noun use of past participle of accedere "to approach," from assimilated form of ad "to" (see ad-) + cedere "go, move, withdraw" (from PIE root *ked- "to go, yield"). The English sense of "an entrance" (c. 1600) is directly from Latin. The meaning "habit or power of getting into the presence of (someone or something)" is from late 14c.

early 14c., "to lay claim to," from Latin acclamare "to cry out at" (in Medieval Latin "to claim"), from ad "to, toward" (see ad-) + clamare "cry out" (from PIE root *kele- (2) "to shout"). The meaning "to applaud" is recorded by 1630s. The spelling has been conformed to claim. Related: Acclaimed; acclaiming; acclamatory.

"corresponding, conformable," early 14c., from Old French acordant "agreeing with," from Medieval Latin accordantem (nominative accordans), present participle of accordare "agree," from Vulgar Latin (see accord (v.)). Related: Accordantly.

early 14c., acheven, "to perform, execute, accomplish;" late 14c., "gain as a result of effort," from Old French achever (12c.) "to finish, accomplish, complete," from phrase à chef (venir) "at an end, finished," or Vulgar Latin *accapare, from Late Latin ad caput (venire); both the French and Late Latin phrases meaning literally "to come to a head," from ad "to" (see ad-) + stem of Latin caput "head" (from PIE root *kaput- "head").

The Lat. caput, towards the end of the Empire, and in Merov[ingian] times, took the sense of an end, whence the phrase ad caput venire, in the sense of to come to an end .... Venire ad caput naturally produced the Fr. phrase venir à chef = venir à bout. ... From this chief, O.Fr. form of chef (q.v.) in sense of term, end, comes the Fr. compd. achever = venir à chef, to end, finish. [Auguste Brachet, "An Etymological Dictionary of the French Language," transl. G.W. Kitchin, Oxford, 1878]

Related: Achieved; achieving.

"cold," early 14c.; see a- (1), here perhaps intensive + cold (adj.). Or it might be literally "a-cooled," from the past participle of the verb acool "to take cold" (late Old English); "to make cold" (15c.).

early 14c., "inferior officer in the church," from Old French acolite or directly from Medieval Latin acolytus (Late Latin acoluthus), from Greek akolouthos "following, attending on," as a noun, "a follower, attendant," literally "having one way," from a- "together with," copulative prefix (see a- (3)), + keleuthos "a way, road, path, course, journey," which is of unknown etymology. The word was in late Old English as acolitus, a Latin form; in early modern English a corrected form acolythe was used.

"legal settlement" of a debt, obligation, etc., early 14c., aquitaunce, from Old French aquitance and Medieval Latin acquietantia; see acquit + -ance.