approval (n.) Look up approval at Dictionary.com
1680s, from approve + -al (2). According to OED, "Rare bef. 1800; now generally used instead of" approvance (1590s, from French aprovance).
approve (v.) Look up approve at Dictionary.com
c.1300, "to demonstrate, prove;" mid-14c., "to attest (something) with authority," from Old French aprover (Modern French approuver) "approve, agree to," from Latin approbare "to assent to as good, regard as good," from ad- "to" (see ad-) + probare "to try, test something (to find if it is good)," from probus "honest, genuine" (see prove).

The meaning extended late 14c. to "to sanction, endorse, confirm formally" then to "assent to (something) as good" (early 15c.), especially in reference to the actions of authorities, parliaments, etc. Related: Approved; approving.
approximate (adj.) Look up approximate at Dictionary.com
early 15c., from Latin approximatus, past participle of approximare "to come near to," from ad- "to" (see ad-) + proximare "come near," from proximus "nearest," superlative of prope "near" (see propinquity).
approximate (v.) Look up approximate at Dictionary.com
early 15c., "to bring or put close," from approximate (adj.). Meaning "to come close" is from 1789. Related: Approximated; approximating.
approximately (adv.) Look up approximately at Dictionary.com
1742, from approximate (adj.) + -ly (2).
approximation (n.) Look up approximation at Dictionary.com
early 15c., "act of coming near or close," noun of action from approximate (v.). Meaning "result of approximating" is from 1650s.
appurtenance (n.) Look up appurtenance at Dictionary.com
c.1300, "right, privilege or possession subsidiary to a principal one," from Anglo-French apurtenance (12c.), Old French apartenance, present participle of apartenir "be related to," from Latin appertinere "to pertain to," from ad- "to" (see ad-) + pertinere "belong to" (see pertain).
appurtenances (n.) Look up appurtenances at Dictionary.com
"apparatus, gear," late 14c.; see appurtenance.
appurtenant (adj.) Look up appurtenant at Dictionary.com
late 14c., from Anglo-French apurtenant, Old French apartenant, present participle of apartenir "be related to" (see appurtenance).
apraxia (n.) Look up apraxia at Dictionary.com
1877, medical Latin, from German apraxie (H. Steinthal, 1871), from Greek apraxia "inaction," from privative prefix a- (see a- (3)) + praxis "a doing, action, business" (see praxis).
apricate (v.) Look up apricate at Dictionary.com
1690s, "to bask in the sun," from Latin apricatus, past participle of apricari "to bask in the sun," from apricus "exposed" (to the sun); perhaps contracted from *apericus, from aperire "to open" (see overt). Transitive sense is recorded from 1851.
apricot (n.) Look up apricot at Dictionary.com
1550s, abrecock, from Catalan abercoc, related to Portuguese albricoque, from Arabic al-birquq, through Byzantine Greek berikokkia from Latin (malum) praecoquum "early-ripening (fruit)" (see precocious). Form assimilated to French abricot.
Latin praecoquis early-ripe, can probably be attributed to the fact that the fruit was considered a variety of peach that ripened sooner than other peaches .... [Barnhart]
The older Latin name for it was prunum Armeniacum or malum Armeniacum, in reference to supposed origin in Armenia. As a color name, first attested 1906.
April Look up April at Dictionary.com
c.1300, aueril, from Old French avril (11c.), from Latin (mensis) Aprilis "(month) of Venus," second month of the ancient Roman calendar, dedicated to the goddess Venus and perhaps based on Apru, an Etruscan borrowing of Greek Aphrodite. In English in Latin form from mid-12c. Replaced Old English Eastermonað, which was similarly named for a fertility goddess. Re-spelled in Middle English on Latin model (apprile first attested late 14c.).
April fool (n.) Look up April fool at Dictionary.com
1680s; April-gowk (from Old Norse gaukr "a cuckoo") is a northern variant. April Fool's Day customs of sending people on false errands seem to have come to England from France late 17c.; originally All Fool's Day (1712). In Cumberland, Westmorland and northern parts of Lancashire and Yorkshire, however, May 1 was the day for hoaxing, and the fool was a May gosling. That custom was first attested 1791.
apron (n.) Look up apron at Dictionary.com
mid-15c., faulty separation (as also in adder, umpire) of a napron (c.1300), from Old French naperon "small table-cloth," diminutive of nappe "cloth," from Latin mappa "napkin." Napron was still in use as recently as late 16c. The shift of Latin -m- to -n- was a tendency in Old French (conter from computare, printemps from primum, natte "mat, matting," from matta). Symbolic of "wife's business" from 1610s. Apron-string tenure was in reference to property held in virtue of one's wife, or during her lifetime only.
Even at his age, he ought not to be always tied to his mother's apron string. [Anne Brontë, "The Tenant of Wildfell Hall," 1848]
apropos (adv.) Look up apropos at Dictionary.com
1660s, "opportunely," from French à propos "to the purpose," from propos "thing said in conversation, talk; purpose, plan," from Latin propositium "purpose," past participle of proponere "to set forth, propose" (see propound). Meaning "as regards" is 1761, from French. As an adjective, "to the point or purpose," from 1690s.
apse (n.) Look up apse at Dictionary.com
"semicircular extension at the end of a church," 1846, from Latin apsis "an arch, a vault," from Greek hapsis (Ionic apsis) "loop, arch," originally "a fastening, felloe of a wheel," from haptein "fasten together," of unknown origin. The original sense in Greek seems to have been the joining of the arcs to form a circle, especially in making a wheel. The architectural term is earlier attested in English in the Latin form (1706).
apsis (n.) Look up apsis at Dictionary.com
"perigree of the moon, perihelion of a planet" (plural apsides), 1650s, from Latin apsis "arch, vault" (see apse).
apt (adj.) Look up apt at Dictionary.com
mid-14c., "inclined, disposed;" late 14c., "suited, fitted, adapted," from Old French ate (13c., Modern French apte), or directly from Latin aptus "fit, suited," adjectival use of past participle of *apere "to attach, join, tie to," from PIE root *ap- (1) "to grasp, take, reach" (cognates: Sanskrit apnoti "he reaches," Latin apisci "to reach after, attain," Hittite epmi "I seize"). Elliptical sense of "becoming, appropriate" is from 1560s.
aptitude (n.) Look up aptitude at Dictionary.com
early 15c., "tendency, likelihood," from Middle French aptitude (14c.) or directly from Late Latin aptitudo (genitive aptitudinis) "fitness," noun of quality from Latin aptus "joined, fitted" (see apt). Meaning "natural capacity to learn" is 1540s; that of "quality of being fit (for a purpose or position)" is from 1640s.
aptly (adv.) Look up aptly at Dictionary.com
early 15c., "by natural means," from apt + -ly (2).
aptness (n.) Look up aptness at Dictionary.com
1530s, from apt + -ness.
aqua (n.) Look up aqua at Dictionary.com
"water," late 14c.; see aqua-. Used in late Middle English in combinations to mean "decoction, solution" (as in aqua regia, a mix of concentrated acids, literally "royal water," so called for its power to dissolve gold and other "noble" metals). As the name of a light greenish-blue color, 1936.
aqua fortis (n.) Look up aqua fortis at Dictionary.com
old name for "concentrated nitric acid," c.1600, Latin, literally "strong water;" see aqua- + fort. So called for its power of dissolving metals (copper, silver) unaffected by other agents.
aqua vitae (n.) Look up aqua vitae at Dictionary.com
early 15c., Latin, literally "water of life," an alchemical term for unrefined alcohol. Applied to brandy, whiskey, etc. from 1540s. Compare whiskey, also French eau-de-vie "spirits, brandy," literally "water of life."
aqua- Look up aqua- at Dictionary.com
word-forming element meaning "water," from Latin aqua "water; the sea; rain," cognate with Proto-Germanic *akhwo, source of Old English ea "river," Gothic ahua "river, waters," Old Norse Ægir, name of the sea-god, Old English ieg "island;" all from PIE *akwa- "water" (cognates: Sanskrit ap "water," Hittite akwanzi "they drink," Lithuanian uppe "a river").
aquacade (n.) Look up aquacade at Dictionary.com
"aquatic entertainment," 1937, American English, from aqua- + -cade, from cavalcade (q.v.).
aquaculture (n.) Look up aquaculture at Dictionary.com
1869, from aqua- + culture (n.).
aqualung (n.) Look up aqualung at Dictionary.com
1950, from aqua- + lung. Developed 1943 by Jacques Cousteau and Emile Gagnan.
aquamarine (n.) Look up aquamarine at Dictionary.com
1590s, agmarine, "bluish-green type of beryl," from French or Provençal, from Latin aqua marina "sea water," from aqua "water" (see aqua-) + marina, fem. of marinus "of the sea" (see marine (adj.)). Apparently first used as a description of a bluish-green color by John Ruskin, 1846. Abbreviation aqua is attested from 1936.
aquanaut (n.) Look up aquanaut at Dictionary.com
1881, from aqua- + ending from Greek nautes "sailor" (see naval).
aquarelle (n.) Look up aquarelle at Dictionary.com
1855, from French aquarelle (18c.), from Italian acquerella "water-color," diminutive of acqua, from Latin aqua "water" (see aqua-).
Aquarian (adj.) Look up Aquarian at Dictionary.com
1940, in the astrological/New Age sense; see Aquarius + -ian.
aquarium (n.) Look up aquarium at Dictionary.com
1830, noun use of neuter of Latin aquarius "pertaining to water," as a noun, "water-carrier," genitive of aqua "water" (see aqua-). The word existed in Latin, but there it meant "drinking place for cattle." Originally especially for growing aquatic plants; An earlier attempt at a name for "fish tank" was marine vivarium.
Aquarius Look up Aquarius at Dictionary.com
faint constellation and 11th zodiac sign, late Old English, from Latin aquarius, literally "water carrier," properly an adjective, "pertaining to water" (see aquarium); a loan-translation of Greek Hydrokhoos "the water-pourer," old Greek name of this constellation.

Aquarians were a former Christian sect that used water instead of wine at the Lord's Supper. Age of Aquarius (1940) is an astrological epoch supposed to have begun in the 1960s, embodying the traits of this sign and characterized by world peace and human brotherhood. The term and the concept probably got a boost in popular use when An Aquarian Exposition was used as the sub-name of the Woodstock Music & Art Fair (1969).
aquatic (adj.) Look up aquatic at Dictionary.com
late 15c., from Middle French and Old French aquatique (13c.), from Latin aquaticus "growing in water; bringing rain," from aqua "water" (see aqua-)
aquatint (n.) Look up aquatint at Dictionary.com
1782, "engraving made with aqua fortis," from Italian acquatinta, from Latin aqua tincta "dyed water;" see aqua- + tinct.
aqueduct (n.) Look up aqueduct at Dictionary.com
1530s, from Latin aquaeductus "conveyance of water," from aquae, genitive of aqua "water" (see aqua-), + ductus "a leading, conducting," past participle of ducere "to lead" (see duke (n.)).
aqueous (adj.) Look up aqueous at Dictionary.com
1640s, from Latin aqua "water" (see aqua-) on analogy of French aqueux "watery" (16c., which, however, is from Late Latin aquosus "abounding in water"). Or by analogy of Latin terreus "earthy," from terra "earth." Aqueous humor is the original use in English.
aquifer (n.) Look up aquifer at Dictionary.com
1897, coined from Latin aqui-, comb. form of aqua "water" (see aqua-) + -fer "bearing," from ferre "to bear" (see infer).
aquiline (adj.) Look up aquiline at Dictionary.com
"curved like an eagle's beak," 1640s, originally in English in reference to long, hooked noses, from Latin aquilinus "of or like an eagle," from aquila "eagle," of uncertain origin, usually explained as "the dark bird;" compare aquilus "blackish, of the color of darkness."
aquiver (adv.) Look up aquiver at Dictionary.com
1864, from a- (1) + quiver (v.).
Arab (n.) Look up Arab at Dictionary.com
late 14c. (Arabes, a plural form), from Old French Arabi, from Latin Arabs (accusative Arabem), from Greek Araps (genitive Arabos), from Arabic 'arab, indigenous name of the people, perhaps literally "inhabitant of the desert" and related to Hebrew arabha "desert." Meaning "homeless little wanderer, child of the street" is from 1848 (originally Arab of the city), in reference to nomadic ways. Arab League formed in Cairo, March 22, 1945.
arabesque (n.) Look up arabesque at Dictionary.com
1610s, "Moorish or Arabic ornamental design," from French arabesque (16c.), from Italian arabesco, from Arabo "Arab," with reference to Moorish architecture. As a ballet pose, first attested 1830. Musical sense, in reference to an ornamented theme, is from 1864, originally the title given by Robert Schumann to one of his piano pieces.
Arabia Look up Arabia at Dictionary.com
1711; see Arab + -ia. The older name for "the country of Arabia" was Araby (late 13c.).
Arabian Look up Arabian at Dictionary.com
c.1300, adjective and noun; see Arab + -ian. As a prized type of horse, it is attested from 1660s. The Arabian bird was the phoenix.
Arabic (adj.) Look up Arabic at Dictionary.com
early 14c., from Old French Arabique (13c.), from Latin Arabicus "Arabic" (see Arab). Old English used Arabisc "Arabish." Originally in reference to gum arabic; noun meaning "Arabic language" is from late 14c.

Arabic numerals (actually Indian) first attested 1727; they were introduced in Europe by Gerbert of Aurillac (later Pope Sylvester II) after a visit to Islamic Spain in 967-970. A prominent man of science, he taught in the diocesan school at Reims, but the numbers made little headway against conservative opposition in the Church until after the Crusades. The earliest depiction of them in English, in "The Crafte of Nombrynge" (c.1350) correctly identifies them as "teen figurys of Inde."
arable (adj.) Look up arable at Dictionary.com
early 15c., "suitable for plowing" (as opposed to pasture- or wood-land), from Old French arable (12c.), from Latin arabilis, from arare "to plow," from PIE *are- "to plow" (cognates: Greek aroun, Old Church Slavonic orja, Lithuanian ariu "to plow;" Gothic arjan, Old English erian, Middle Irish airim, Welsh arddu "to plow;" Old Norse arþr "a plow"). Replaced by late 18c. native erable, from Old English erian "to plow," from the same PIE source.
arachnid (n.) Look up arachnid at Dictionary.com
"a spider," 1869, from French arachnide (1806) or Modern Latin Arachnida, introduced as name for this class of arthropods 1815 by French biologist Jean Baptiste Pierre Antoine de Monet de Lamarck (1744-1829), from Greek arakhne (fem.) "spider; spider's web," which probably is cognate with Latin aranea "spider, spider's web" (borrowed in Old English as renge "spider"), from aracsna. The Latin word could be a Greek borrowing or both could be from a common root. An earlier noun form was arachnidian (1828).
arachnoid (adj.) Look up arachnoid at Dictionary.com
"cobweb-like," especially of the membrane around the brain and spinal cord, 1789, from Modern Latin arachnoides, from Greek arakhnoeides "cobweb-like," from arakhne "cobweb" (see arachnid) + -oeides (see -oid).