Online Etymology Dictionary

interrogate (v.): late 15c., a back-formation from interrogation or else from Latin interrogatus, past participle of interrogare "to ask, question." The Old French word was interroger (14c.) which yielded English interroge (late 15c.), now obsolete. Related: Interrogated; interrogating.
erupt (v.): 1650s, of diseases, etc., from Latin eruptus, past participle of erumpere "to break out, burst," from assimilated form of ex- "out" (see ex-) + rumpere "to break, rupture" (see rupture (n.)). Of volcanoes, from 1770 (the Latin word was used in reference to Mount Etna). Related: Erupted; erupting.
-esque: word-forming element meaning "resembling or suggesting the style of," from French -esque "like, in the manner of," from Italian -esco, which, with Medieval Latin -iscus, is from Frankish or some other Germanic source (compare Old High German -isc, German -isch; see -ish).
freedman (n.): "manumitted slave," c. 1600, from past participle of free (adj.) + man (n.). Especially in U.S. history. The older word is freeman. Freedman's Bureau (1865) was the popular name of the Bureau of Refugees, Freedmen, and Abandoned Lands, established by Congress March 3, 1865, and discontinued in 1872.
fuller (n.): "one who fulls cloth," Old English fullere "fuller" (Mark ix:3), from Latin fullo "fuller" (see foil (v.)). The native word is walker. Fuller's earth (silicate of alumina) is recorded by 1520s; so called because it was used in cleansing cloth.
-fuge: word-forming element meaning "that which drives away or out," from Modern Latin -fugus, with sense from Latin fugare "to put to flight" (see febrifuge) but form from Latin fugere "to flee" (see fugitive (adj.)).
exorable (adj.): 1570s, "susceptible of being moved by entreaty" (a word much rarer than its opposite and probably existing now only as a back-formation from it), from Latin exorabilis "easily entreated, influenced by prayer," from exorare "to persuade" (see inexorable). Related: Exorably.
extroversion (n.): mid-17c., "condition of being turned inside out," noun of action from obsolete verb extrovert (v.) "to turn inside out," from extro- + Latin vertere (see versus). Earliest as a word in mysticism; modern use in psychology attested by 1920.
fichu (n.): "scarf, neckerchief, small, triangular piece forming part of a woman's dress," 1803, from French fichu (18c. in this sense), apparently a noun use of the adjective fichu "carelessly thrown on," from Latin figere "to fasten" (see fix (v.)). "[M]od. substitution for a coarser word" [Weekley].
gardener (n.): late 13c. (early 12c. as a surname), from Old North French *gardinier (Old French jardineor "gardener," 12c., Modern French jardinier), from gardin "(kitchen) garden" (see garden (n.)). Compare German Gärtner. An Old English word for it was wyrtweard, literally "plant-guard."
gastro-: also gastero-, scientific word-forming element meaning "stomach," before vowels gastr-, from Greek gastro-, comb. form of gaster (genitive gastros) "belly, paunch; womb" (see gastric). Also used in compounds in ancient Greek, as gastrobarys "heavy with child."
feist (n.): also fist, "a breaking wind, foul smell, fart," mid-15c. (Old English had present participle fisting, glossing Latin festiculatio), a general West Germanic word with cognates in Middle Dutch veest, Dutch vijst; see feisty.
calque (n.): "loan translation of a foreign word or phrase," from French calque, literally "a copy," from calquer "to trace by rubbing" (itself borrowed in English 1660s as calk), introduced 16c. from Italian calcare, from Latin calcare "to tread, to press down."
interglacial (adj.): 1867 in reference to warm spells between ice ages, from German, coined 1865 by Swiss naturalist Oswald Heer (1809-1883); see inter- "between" + glacial. The word was used earlier in reference to situations between glaciers or ice caps (1835).
jarhead (n.): also jar-head, "U.S. Marine," by 1985 (but in a biographical book with a World War II setting), from jar + head (n.). Also used as a general term of insult (by 1979) and by 1922 as a Georgia dialectal word for "mule."
kerato-: before vowels, kerat-, scientific word-forming element meaning "horn, horny," also "cornea of the eye" (see cornea), from Greek keras (genitive keratos) "the horn of an animal; horn as a material," from PIE *ker- (1) "horn, head" (see horn (n.)).
lack (v.): "be wanting or deficient" (intransitive), late 12c., perhaps from Middle Dutch laken "to be wanting," from lak (n.) "deficiency, fault," or an unrecorded native cognate word (see lack (n.)). Transitive sense "be in want of" is from early 13c. Related: Lacked; lacking.
lax (n.): "salmon," from Old English leax (see lox). Cognate with Middle Dutch lacks, German Lachs, Danish laks, etc.; according to OED the English word was obsolete except in the north and Scotland from 17c., reintroduced in reference to Scottish or Norwegian salmon.
languet (n.): "something in the shape of a little tongue," early 15c., from Old French languete (Modern French languette), literally "little tongue," diminutive of langue "tongue," from Latin lingua "tongue" (see lingual). As the name of a kind of hood in 17c. women's dress it probably is a separate borrowing of the French word.
cist (n.): "sepulchral chest or chamber," 1804, in some cases from Latin cista "wickerwork basket, box," from Greek kiste "box, chest" (see chest); according to OED, in some cases from Welsh cist in cist faen "stone coffin," the first element of which is from the Latin word.
Capsicum (n.): genus of pepper plants, 1660s, of unknown origin, a word said to have been chosen by French botanist Joseph Pitton de Tournefort (1656-1708); perhaps irregularly formed from Latin capsa "box" (see case (n.2)).
Catawba (n.): type of American grape, 1857, the name is that of a river in South Carolina, U.S., where the grape was found. The river is named for the Katahba Indian group and language (Siouan), from katapu "fork of a stream," itself a Muskogean loan-word.
croupier (n.): "one who clears the winnings from the table in gambling," 1731, from French croupier (17c.), originally one who rides behind another, on the croup or "rump" of a horse (a word of Germanic origin); hence extended to any one who backs up another; a "second."
crypto-: before vowels crypt-, word-forming element meaning "secret" or "hidden," used in forming English words since at least 1760, from Latinized form of Greek kryptos "hidden, concealed, secret" (see crypt; the Greek comb. form was krypho-). Crypto-fascist is attested from 1937; crypto-communist from 1946.
Curacao: West Indian island, Curaçao, discovered 1499 by Alonso de Hojeda, who called it Isla de los Gigantes in reference to the stature of the natives. The modern name probably is a Europeanized version of some lost native word. The liqueur is made from the dried peel of the Curaçao orange.
cordovan (n.): 1590s, "fine Spanish leather," from adjective Cordovan, from Spanish cordovan (modern cordoban), from cordovano (adj.) "of Cordova," the Spanish city, former capital of Moorish Spain; a later adoption of the same word that became cordwain (see cordwainer). The city name is from Phoenician qorteb "oil press."
corticosteroid (n.): by 1945, from cortico-, word-forming element from comb. form of Latin cortex "bark of a tree" (see cortex), applied since c. 1890 to various surface structures of plants, animals, or organs + steroid. So called because they are produced in the adrenal cortex. Related: Corticosterone.
deipnosophist (n.): "gourmand," 1650s, from Greek deipnosophistes "one learned in the mysteries of the kitchen," from deipnon "chief meal, dinner" (which is of unknown origin) + sophistes "master of a craft" (see sophist). the word has come down thanks to "Deipnosophistai," 3c. work on gastronomy by Athenaeus.
demarche (n.): 1650s, "walk, step," from French démarche (15c.) literally "gait, walk, bearing," from démarcher (12c.) "to march," from de- (see de-) + marcher (see march (v.)). Meaning "a diplomatic step" attested from 1670s. A word never quite nativized.
craftsman (n.): mid-14c., craftes man, originally "a member of a craft guild," from genitive of craft (n.) + man (n.1). Written as one word from late 14c. Old English had cræftiga in this sense. Related: Craftsmanship.
credentials (n.): "letters entitling the bearer to certain credit or confidence," 1670s, from Medieval Latin credentialis, from credentia (see credence). Probably immediately as a shortening of letters credential (1520s, with French word order); earlier was letter of credence (mid-14c.).
crestfallen (adj.): 1580s, past participle adjective, but the verb crestfall is recorded only from 1610s, in reference to diseased horses, and is rare. It's possible that the image behind this use of the word is not cocks, as often is asserted, but horses.
deferent (adj.): 1620s, from French déférent (16c.), from Latin deferentem (nominative deferens), present participle of deferre "to carry down or away" (see defer (v.2)). Earlier in Middle English as a word in astronomy (early 15c.).
cyan (n.): 1889, short for cyan blue (1879), from Greek kyanos "dark blue, dark blue enamel, lapis lazuli," probably a non-Indo-European word, but perhaps akin to, or from, Hittite *kuwanna(n)- "copper blue."
cutpurse (n.): "one who steals by the method of cutting purses, a common practice when men wore their purses at their girdles" [Johnson], mid-14c., from cut (v.) + purse (n.). The word continued after the method switched to picking pockets.
elfin (adj.): "of or pertaining to elves," 1590s, from elf; first found in Spenser, who also used it as a noun and might have been thinking of elven but the word also is a proper name in the Arthurian romances (Elphin).
-en (1): word-forming element making verbs (such as darken, weaken) from adjectives or nouns, from Old English -nian, from Proto-Germanic *-inojan (also source of Old Norse -na), from PIE adjectival suffix *-no-. Most active in Middle English.
earnings (n.): amount of money one makes (from labor or investment), 1732, from plural of verbal noun earning, from earn (v.). Old English had earnung in sense "fact of deserving; what one deserves; merit, reward, consideration, pay," but the modern word seems to be a new formation.
-eer: noun word-forming element meaning "one who" (operates, produces, deals in); Englished form of French -ier, from Latin -arius, -iarius; compare -ary. Usually in English words of more recent borrowing from French; older words tend to keep -ier.
teenager (n.): also teen ager, teen-ager; 1922, derived noun from teenage (q.v.). The earlier word for this was teener, attested in American English from 1894, and teen had been used as a noun to mean "teen-aged person" in 1818, though this was not common before 20c.
Che: nickname of Argentine Marxist revolutionary Ernesto Guevara (1928-1967), acquired when he was working with Cuban exiles in Guatemala in mid-1950s, from his dialectal use of Argentine che, a slang filler word in speech.
chelicerae (n.): 1831, plural of Modern Latin chelicera, from Greek khele "crab claw, talon, pincers; cloven hoof of cattle, horse's hoof," metaphorically "surgical forceps, hooked needle, crochet needle, notch of an arrow," a word of uncertain origin with no agreement on ulterior connections. Earlier chelicer (1835), from French chélicère.
choate (adj.): "finished, complete," mistaken back-formation from inchoate (q.v.) as though that word contained in- "not." First attested 1878 in letter from Oliver Wendell Holmes lamenting barbarisms in legal case writing (he said he found choate in a California report).
compiler (n.): early 14c., from Anglo-French compilour, Old French compileur "author, chronicler," from Latin compilatorem, agent noun from compilare (see compile). Another form of the word current in early Modern English was compilator, directly from the Latin.
concent (n.): "harmony," 1580s, from Latin concentus "a singing together, harmony," from concinere "to sing or sound together," from com- "with, together" (see com-) + canere "to sing" (see chant (v.)). Often misspelled consent or confused with that word.
Congo: African nation, named for the river that runs through it, which is from a Bantu word meaning "mountains" (i.e., the river that flows from the mountains). As an adjective, Congoese is native English (1797) but has been supplanted by Congolese (1900), from French Congolais.
Caucasus (n.): mountain range between Europe and the Middle East, from Latin Caucasus, from Greek kaukasis, said by Pliny ("Natural History," book six, chap. XVII) to be from a Scythian word similar to kroy-khasis, literally "(the mountain) ice-shining, white with snow." But possibly from a Pelasgian root *kau- meaning "mountain."
centerfold (n.): also center-fold, "fold-out center spread of a magazine or newspaper," 1950, from center (n.) + fold (n.2). "Playboy" debuted December 1953, and the word came to be used especially for illustrations of comely women, hence "woman who poses as a centerfold model" (by 1965).
certiorari: legal Latin, "to be certified, to be informed or shown," from a word figuring in the opening phrase of such writs from superior to inferior courts seeking the records of a case. Passive present infinitive of certorare "to certify, inform," from certior, comp. of certus "sure" (see certain).
chad (n.3): "hanging flap or piece after a hole is punched in paper," a word unknown to most people until the 2000 U.S. presidential election (when the outcome hinged on partially punched paper ballots in some Florida counties), attested by 1930, of unknown origin.