actuarial (adj.) Look up actuarial at
"of the business of an actuary," 1853, from actuary + -al (1). Related: Actuarially.
actuary (n.) Look up actuary at
1550s, "registrar, clerk," from Medieval Latin actuarius "copyist, account-keeper, short-hand writer," from Latin actus in the specialized sense "public business" (literally "a doing;" see act (n.)). Meaning "person skilled in the calculation of chances and costs," especially as employed by an insurer, is from 1849.
actuate (v.) Look up actuate at
1590s, "perform" (a sense now obsolete), from Medieval Latin actuatus, past participle of actuare "perform, put into action," from Latin actus "a doing" (see act (n.)). Sense of "put into action, inspire with activity" is from 1640s. Related: Actuated; actuating.
actuation (n.) Look up actuation at
"a putting in motion, communication of force," 1620s, noun of action from actuate (v.).
acuity (n.) Look up acuity at
"sharpness, acuteness," early 15c., from Old French acuite (14c.) or directly from Medieval Latin acuitatem (nominative acuitas) "sharpness," noun of state from Latin acuere "to sharpen," literal and figurative (of intellect, emotion, etc.), related to acus "a needle," from PIE root *ak- "rise to a point, be sharp" (see acro-).
acumen (n.) Look up acumen at
"quickness of perception, keen insight," 1530s, from Latin acumen "a point, sting," hence, figuratively, "mental sharpness, shrewdness," from acuere "to sharpen," literal and figurative (of intellect, emotion, etc.), related to acus "a needle," from PIE root *ak- "rise to a point, be sharp" (see acro-). Related: Acuminous.
acuminate (adj.) Look up acuminate at
1640s, "having a long, tapering end" (of certain feathers, leaves, etc.), from Latin acuminatus, past participle of acuminare "to sharpen," from acumen "a point" (see acumen). Related: Acuminated; acumination.
acupressure (n.) Look up acupressure at
1859, name of a method (developed by J.Y. Simpson) of stopping surgical bleeding by pinning or wiring the artery shut, from Latin acus "needle" (see acuity) + pressure (n.). From 1958 in reference to the oriental body therapy also known as shiatsu (said to mean literally "Finger-pressure" in Japanese).
acupuncture (n.) Look up acupuncture at
1680s, "pricking with a needle" as a surgical operation to ease pain, from Latin acus "a needle" (from PIE root *ak- "rise to a point, be sharp;" see acro-) + puncture. The verb is first recorded 1972.
acupuncturist (n.) Look up acupuncturist at
1843, from acupuncture + -ist.
acute (adj.) Look up acute at
late 14c., originally of fevers and diseases, "coming quickly to a crisis" (opposed to chronic), from Latin acutus "sharp, pointed," figuratively "shrill, penetrating; intelligent, cunning," past participle of acuere "to sharpen" (literal and figurative), from PIE root *ak- "rise to a point, be sharp" (see acro-). Also used of humors (early 15c.). Meaning "ending in a sharp point" is from 1560s; sense of "sharp or penetrating in intellect" is from 1580s. OF feelings, pains, etc., "intense," 1727. As a noun, early 15c. of fevers; c. 1600 as "acute accent." Related: Acutely; acuteness.
ad (n.) Look up ad at
abbreviation of advertisement, attested by 1841. Long resisted by those in the trade, and according to Mencken (1945) denounced by William C. D'Arcy (president of Associated Advertising Clubs of the World) as "the language of bootblacks, ... beneath the dignity of men of the advertising profession."
ad hoc Look up ad hoc at
Latin phrase, "to this, with respect to this, for this (specific purpose)," from ad "to" (see ad-) + hoc, neuter accusative of hic "this." Hence, "appointed or enacted for some particular purpose" (1879).
ad hominem Look up ad hominem at
c. 1600, Latin, literally "to a man," from ad "to" (see ad-) + hominem, accusative of homo "man" (see homunculus). Hence, "to the interests and passions of the person." Originally an argument or appeal to the known preferences or principles of the person addressed.
ad infinitum Look up ad infinitum at
"endlessly," Latin, literally "to infinity" from ad "to, unto" (see ad-) + infinitum "infinity," neuter accusative of adjective infinitus "endless" (see infinite). English version to infinity is attested from 1630s.
ad lib Look up ad lib at
1811, shortened from Latin ad libitum "at one's pleasure, as much as one likes" (c. 1600), from ad "to" (see ad-) + libitum, accusative of libere "to please" (see libido). First recorded as one word 1919 (v.), 1925 (n.).
ad nauseam Look up ad nauseam at
"to a sickening extent," Latin, literally "to sickness," from ad "to" (see ad-) + nauseam, accusative of nausea (see nausea).
ad valorem Look up ad valorem at
type of customs duties, 1711, Modern Latin, "(in proportion) to the value," from ad "to" (see ad-) + Late Latin valorem, accusative of valor "value" (see value (n.)).
ad- Look up ad- at
word-forming element expressing direction toward or in addition to, from Latin ad "to, toward" in space or time; "with regard to, in relation to," as a prefix, sometimes merely emphatic, from PIE *ad- "to, near, at" (cognate with Old English æt; see at). Simplified to a- before sc-, sp- and st-; modified to ac- before many consonants and then re-spelled af-, ag-, al-, etc., in conformity with the following consonant (as in affection, aggression). In Old French, reduced to a- in all cases (an evolution already underway in Merovingian Latin), but written forms in French were refashioned after Latin in 14c. and English did likewise 15c. in words it had picked up from Old French. In many cases pronunciation followed the shift.
Ada Look up Ada at
fem. proper name, from Hebrew Adha, literally "ornament."
adage (n.) Look up adage at
"brief, familiar proverb," 1540s, Middle French adage, from Latin adagium "adage, proverb," apparently from adagio, from ad- "to" (see ad-) + *agi-, root of aio "I say," from PIE *ag- (2) "to speak." But Tucker thinks the second element is rather ago "set in motion, drive, urge."
adagio (adv.) Look up adagio at
c. 1746, in music, "slowly, leisurely and gracefully," Italian, from ad agio, from ad "to, at" (see ad-) + agio "leisure," from Vulgar Latin adiacens, present participle of adiacere "to lie at, to lie near" (compare adjacent). In noun sense of "a slow movement," first attested 1784.
Adam Look up Adam at
masc. proper name, Biblical name of the first man, progenitor of the human race, from Hebrew adam "man," literally "(the one formed from the) ground" (Hebrew adamah "ground"); compare Latin homo "man," humanus "human," humus "earth, ground, soil." To not know (someone) from Adam "not know him at all" is first recorded 1784.
Adam's apple (n.) Look up Adam's apple at
1731, corresponding to Latin pomum Adami, perhaps an inexact translation of Hebrew tappuah haadam, literally "man's swelling," from ha-adam "the man" + tappuah "anything swollen." The reference is to the legend that a piece of the forbidden fruit (commonly believed to be an apple) that Eve gave Adam stuck in his throat. The term is mentioned in early 15c. as the name of an actual oriental and Mediterranean fruit, a variety of lime with an indentation fancied to resemble the marks of Adam's teeth.
adamant (adj.) Look up adamant at
late 14c., "hard, unbreakable," from adamant (n.). Figurative sense of "unshakeable" first recorded 1670s. Related: Adamantly; adamance.
adamant (n.) Look up adamant at
mid-14c., from Old French adamant and directly from Latin adamantem (nominative adamas) "adamant, hardest iron, steel," also figuratively, of character, from Greek adamas (genitive adamantos) "unbreakable, inflexible" metaphoric of anything unalterable, also the name of a hypothetical hardest material, perhaps literally "invincible," from a- "not" + daman "to conquer, to tame" (see tame (adj.)), or else a word of foreign origin altered to conform to Greek.

Applied in antiquity to a metal resembling gold (Plato), white sapphire, magnet (by Ovid, perhaps via confusion with Latin adamare "to love passionately"), steel, emery stone, and especially diamond (see diamond). "The name has thus always been of indefinite and fluctuating sense" [Century Dictionary]. The word was in Old English as aðamans "a very hard stone."
adamantine (adj.) Look up adamantine at
c. 1200, from Latin adamantinus "hard as steel, inflexible," from Greek adamantinos, from adamas (see adamant (n.)).
Adamite (n.) Look up Adamite at
"human being, descendant of Adam" the Biblical first man, 1630s, from Adam + -ite (1). Used from 1620s in reference to sects or groups that practice nudism, in reference to the state of Adam before the Fall.
adapt (v.) Look up adapt at
early 15c. (implied in adapted) "to fit (something, for some purpose)," from Middle French adapter (14c.), from Latin adaptare "adjust," from ad- "to" (see ad-) + aptare "to join," from aptus "fitted" (see apt). Meaning "to undergo modification so as to fit new circumstances" (intransitive) is from 1956. Related: Adapting.
adaptability (n.) Look up adaptability at
1660s, from adapt + -ability.
adaptable (adj.) Look up adaptable at
1800, from adapt + -able.
adaptation (n.) Look up adaptation at
c. 1600, "action of adapting," from French adaptation, from Late Latin adaptationem (nominative adaptatio), noun of action from past participle stem of adaptare "to adjust" (see adapt). Meaning "condition of being adapted" is from 1670s. Sense of "modification of a thing to suit new conditions" is from 1790. Biological sense first recorded 1859 in Darwin's writings.
adapter (n.) Look up adapter at
1801, agent noun from adapt. Electrical engineering sense from 1907.
add (v.) Look up add at
late 14c., "to join or unite (something to something else)," from Latin addere "add to, join, attach, place upon," from ad- "to" (see ad-) + -dere comb. form meaning "to put, place," from dare "to give" (see date (n.1)). Meaning "to do sums, do addition" also is from late 14c. Related: Added; adding. To add up "make sense" is from 1942.
add-on (n.) Look up add-on at
"additional component," 1941, from add (v.) + on.
added (adj.) Look up added at
"additional," c. 1600, past participle adjective from add (v.).
addendum (n.) Look up addendum at
1794, literally "something added," from Latin addendum, neuter of addendus "that which is to be added," gerundive of addere (see add (v.)). Classical plural form is addenda.
adder (n.) Look up adder at
Old English næddre "a snake, serpent, viper," from Proto-Germanic *nædro "a snake" (source also of Old Norse naðra, Middle Dutch nadre, Old High German natra, German Natter, Gothic nadrs), from PIE root *netr- (source also of Latin natrix "water snake," probably by folk-association with nare "to swim;" Old Irish nathir, Welsh neidr "adder").

The modern form represents a faulty separation 14c.-16c. into an adder, for which see also apron, auger, nickname, humble pie, umpire. Nedder is still a northern English dialect form. Folklore connection with deafness is via Psalms lviii.1-5. The adder is said to stop up its ears to avoid hearing the snake charmer called in to drive it away. Adderbolt (late 15c.) was a former name for "dragonfly."
addict (v.) Look up addict at
1530s (implied in addicted), from Latin addictus, past participle of addicere "to deliver, award, yield; give assent, make over, sell," figuratively "to devote, consecrate; sacrifice, sell out, betray" from ad- "to" (see ad-) + dicere "say, declare" (see diction), but also "adjudge, allot." Earlier in English as an adjective, "delivered, devoted" (1520s). Related: Addicted; addicting.
addict (n.) Look up addict at
1909, in reference to morphine, from addict (v.).
addicted (adj.) Look up addicted at
1530s, "delivered over" by judicial sentence; past participle adjective from addict (v.). Modern sense of "dependent" is short for self-addicted "to give over or award (oneself) to someone or some practice" (1560s; exact phrase from c. 1600); specialization to narcotics dependency is from c. 1910.
addiction (n.) Look up addiction at
c. 1600, "tendency," of habits, pursuits, etc.; 1640s as "state of being self-addicted," from Latin addictionem (nominative addictio) "an awarding, a devoting," noun of action from past participle stem of addicere (see addict (v.)). Earliest sense was less severe: "inclination, penchant," but this has become obsolete. In main modern sense it is first attested 1906, in reference to opium (there is an isolated instance from 1779, with reference to tobacco).
addictive (adj.) Look up addictive at
1815, a word in chemistry and medicine; 1939 in the narcotics sense, from addict (v.) + -ive. Related: Addictively; addictiveness.
addition (n.) Look up addition at
late 14c., "action of adding numbers;" c. 1400, "that which is added," from Old French adition "increase, augmentation" (13c.), from Latin additionem (nominative additio) "an adding to, addition," noun of action from past participle stem of addere (see add). Phrase in addition to "also" is from 1680s.
additional (adj.) Look up additional at
1640s, from addition + -al (1). Related: Additionally.
additive (adj.) Look up additive at
1690s, "tending to be added," from Latin additivus "added, annexed," from past participle stem of addere (see addition).
additive (n.) Look up additive at
"something that is added" to a chemical solution or food product, 1945, from additive (adj.).
addle (v.) Look up addle at
1712, from addle (n.) "urine, liquid filth," from Old English adela "mud, mire, liquid manure" (cognate with Old Swedish adel "urine," Middle Low German adel, Dutch aal "puddle").

Used in noun phrase addle egg (mid-13c.) "egg that does not hatch, rotten egg," literally "urine egg," a loan-translation of Latin ovum urinum, which is itself an erroneous loan-translation of Greek ourion oon "putrid egg," literally "wind egg," from ourios "of the wind" (confused by Roman writers with ourios "of urine," from ouron "urine"). Because of this usage, from c. 1600 the noun in English was taken as an adjective meaning "putrid," and thence given a figurative extension to "empty, vain, idle," also "confused, muddled, unsound" (1706). The verb followed a like course. Related: Addled; addling.
address (v.) Look up address at
early 14c., "to guide or direct," from Old French adrecier "go straight toward; straighten, set right; point, direct" (13c.), from Vulgar Latin *addirectiare "make straight," from Latin ad "to" (see ad-) + *directiare, from Latin directus "straight, direct" (see direct (v.)). Late 14c. as "to set in order, repair, correct." Meaning "to write as a destination on a written message" is from mid-15c. Meaning "to direct spoken words (to someone)" is from late 15c. Related: Addressed; addressing.
address (n.) Look up address at
1530s, "dutiful or courteous approach," from address (v.) and from French adresse. Sense of "formal speech" is from 1751. Sense of "superscription of a letter" is from 1712 and led to the meaning "place of residence" (1888).