Online Etymology Dictionary

jelly (v.): c.1600, from jelly (n.). Related: Jellied; jellying.
jellybean (n.): 1905, from jelly (n.) + bean (n.). So called for its shape. Soon used in U.S. slang for "stupid person," probably encouraged by the slang sense of bean as "head."
jellyfish (n.): popular name of the medusa and similar sea-creatures, 1796, from jelly (n.) + fish (n.). Earlier it had been used of a type of actual fish (1707).
jellyroll (n.): also jelly-roll, "cylindrical cake containing jelly or jam," 1873, from jelly + roll (n.). As slang for "vagina, sexual intercourse" it dates from 1914 ("St. Louis Blues").
Jemima: fem. personal name, biblical daughter of Job, from Hebrew Yemimah, literally "dove" (cf. Arabic yamama). The Aunt Jemima ready-mix food product in U.S. dates from 1889.
Jemmy: a popular pet form of the masc. proper name James (in Middle English records, Gemme, Jemme are more common than Jimme). In mid-18c. often associated with effeminacy and male fastidiousness. As "a crowbar" from 1811.
jennet (n.): "small Spanish horse," mid-15c., from French genet, from Spanish jinete "a light horseman," perhaps from Arabic Zenata, name of a Barbary tribe [Klein]. Sense transferred in English and French from the rider to the horse.
Jennifer: fem. proper name, from Welsh Gwenhwyvar, from gwen "fair, white" + (g)wyf "smooth, yielding." The most popular name for girls born in America 1970-1984; all but unknown there before 1938. Also attested as a surname from late 13c.
Jenny: fem. personal name, originally diminutive of Jane or Janet; attested from c.1600 as female equivalent of jack (n.), and like it applied to animals (e.g. Jenny wren, 1640s) and machinery (spinning jenny, 1783).
jeopardise (v.): chiefly British English spelling of jeopardize; for suffix, see -ize. Related: Jeopardised; jeopardising.
jeopardize (v.): 1640s, from jeopardy + -ize. Related: Jeopardized; jeopardizing. As a verb, Middle English used simple jeopard (late 14c.).
jeopardy (n.): c.1300, ioparde (13c. in Anglo-French), from Old French jeu parti, literally "a divided game, game with even chances," from jeu "a game" (from Latin iocus "jest;" see joke (n.)) + parti, past participle of partir "to divide" (see part (v.)). Originally "a stratagem;" sense of "danger, risk" is late 14c.
Jephthah: biblical judge of Israel, from Greek Iephthae, from Hebrew Yiphtah, literally "God opens," imperfective of pathah "he opened" (cf. pethah "opening, entrance").
jerboa (n.): small desert rodent, 1660s, Modern Latin, from Arabic jarbu "flesh of the loins," also the name of a small jumping rodent of North Africa. Cf. gerbil.
jeremiad (n.): 1780, from French jérémiade (1762), in reference to "Lamentations of Jeremiah" in Old Testament.
Jeremiah: masc. proper name, Old Testament prophet (see jeremiad) who flourished c.626-586 B.C.E., from Late Latin Jeremias, from Hebrew Yirmeyah, probably literally "may Jehovah exalt," but Klein suggests it also might be short for Yirmeyahu "the Lord casts, the Lord founds," and compares the first element in Jerusalem. The vernacular form in English was Jeremy.
Jeremy: popular anglicized form of Jeremiah; cf. French Jérémie.
Jericho: Biblical city (Num. xxii:1, etc.), perhaps ultimately from Hebrew yareakh "moon, month," and thus a reference to an ancient moon cult. As a figurative place of retirement (17c.), the reference is to II Sam. x:5.
jerk (v.1): "to pull," 1540s, "to lash, strike as with a whip," of uncertain origin, perhaps echoic. Related: Jerked; jerking.
jerk (v.2): as a method of preserving meat, 1707, American English, from American Spanish carquear, from charqui (see jerky). Related: Jerked.
jerk (n.2): "tedious and ineffectual person," 1935 (the lyric in "Big Rock Candy Mountain" apparently is "Where they hung the Turk [not jerk] that invented work"), American English carnival slang, of uncertain origin. Perhaps from jerkwater town (1878), where a steam locomotive crew had to take on boiler water from a trough or a creek because there was no water tank [Barnhart, OED]. This led 1890s to an adjectival use of jerk as "inferior, insignificant." Alternatively, or influenced by, verbal phrase jerk off "masturbate" [Rawson].
jerk (n.1): 1550s, "stroke of a whip," from jerk (v.1). Sense of "sudden sharp pull or twist" first recorded 1570s. Meaning "involuntary spasmodic movement of limbs or features" first recorded 1805. As the name of a popular dance, it is attested from 1966. Sense in soda jerk attested from 1883, from the pulling motion required to work the taps.
jerk off (v.): slang, "perform male masturbation," by 1896, from jerk (v.) denoting rapid pulling motion + off. Farmer & Henley also list as synonyms jerk (one's) jelly and jerk (one's) juice. The noun jerk off or jerkoff as an emphatic form of jerk (n.) is attested by 1968. As an adjective from 1957.
jerkin (n.): 1510s, of uncertain origin, perhaps related to Dutch jurk "a frock," but this is a modern word, itself of unknown origin, and the initial consonant presents difficulties (Dutch -j- typically becomes English -y-).
jerky (n.): 1850, American English, from American Spanish charqui "jerked meat," from Quechua (Inca) ch'arki "dried flesh."
jerky (adj.): "characterized by jerks," 1858, from jerk (v.1) + -y (2). Related: Jerkily; jerkiness.
jeroboam (n.): 1816, "large wine bottle," from Jeroboam, "a mighty man of valour" (I Kings xi:28) "who made Israel to sin" (xiv:16), from Hebrew Yarobh'am, literally "let the people increase."
Jerome: masc. proper name, from French Jérome, from Late Latin Hieronymus, from Greek Hieronymos, literally "holy name," from hieros "holy" (see ire) + onyma, dialectal form of onoma "name" (see name (n.)).
Jerry (n.): World War I British Army slang for "a German, the Germans," 1919, probably an alteration of German, but also said to be from the shape of the German helmet, which was thought to resemble a jerry, British slang for "chamber pot" (1827), this being probably an abbreviation of jeroboam. Hence jerry-can "5-gallon metal container" (1943), a type first used by German troops in World War II, later adopted by the Allies.
jerry-built (adj.): 1869, in which jerry has a sense of "bad, defective," probably a pejorative use of the male nickname Jerry (a popular form of Jeremy; cf. Jerry-sneak, mid-19c., "sneaking fellow, a hen-pecked husband" [OED]). Or from or influenced by nautical slang jury "temporary," which came to be used of all sorts of makeshift and inferior objects (see jury (adj.)).
jersey (n.): 1580s as a type of knitted cloth; 1842 as a breed of cattle; both from Jersey, one of the Channel Islands. Its name is said to be a corruption of Latin Caesarea, the Roman name for the island (or another near it), influenced by Old English ey "island;" but perhaps rather a Viking name (perhaps meaning "Geirr's island"). The meaning "woolen knitted close-fitting tunic," especially one worn during sporting events, is from 1836.
Jerusalem: holy city in ancient Palestine, from Greek Hierousalem, from Hebrew Yerushalayim, literally "foundation of peace," from base of yarah "he threw, cast" + shalom "peace." Jerusalem "artichoke" is folk etymology of Italian girasole "sunflower."
jess (n.): leg-strap used in hawking and falconry, mid-14c., from Old French jes "straps fastened round the legs of a falcon," plural of jet, literally "cast, throw," from Latin iactus "a throw, cast," from iacere (see jet (v.)). Related: Jesses.
jessamine (n.): Middle English, from Middle French jassemin, variant of jasmine.
Jesse: masc. proper name, biblical father of David, from Latin, from Greek Iessai, from Hebrew Yishay, of unknown origin.
Jessica: fem. proper name, from Late Latin Jesca, from Greek Ieskha, from Hebrew Yiskah, name of a daughter of Haran (Gen. xi:29). Among the top 5 popular names for girls born in the U.S. every year between 1977 and 1997. The familiar form Jessie was one of many fem. names used 20c. for "cowardly or effeminate male."
jest (n.): early 13c., geste, "narrative of exploits," from Old French geste "action, exploit," from Latin gesta "deeds," neuter plural of gestus, past participle of gerere "to carry, behave, act, perform" (see gest). Sense descended through "idle tale" (late 15c.) to "mocking speech, raillery" (1540s) to "joke" (1550s).
jest (v.): 1520s, "to speak in a trifling manner;" 1550s, "to joke," from Middle English gesten "recite a tale" (late 14c.), from geste (see jest (n.)). Sense of "to speak in a trifling manner" is from 1520s. Related: Jested; jesting.
jester (n.): mid-14c., jestour (Anglo-Latin), late 14c., gestour "a minstrel, professional reciter of romances," agent noun from gesten "recite a tale," which was a jester's original function (see jest). Sense of "buffoon in a prince's court" is from c.1500.
Jesuit: 1540s, from Modern Latin Jesuita, member of the Society of Jesus, founded 1533 by Ignatius Loyola to combat Protestantism. Their enemies (in both Catholic and Protestant lands) accused them of belief that ends justify means, hence the sense "a dissembling person" (1630s), and jesuitical "deceitful" (1610s).
Jesus: late 12c. (Old English used hælend "savior"), from Greek Iesous, which is an attempt to render into Greek the Aramaic proper name Jeshua (Hebrew Yeshua) "Jah is salvation," a common Jewish personal name, the later form of Hebrew Yehoshua (see Joshua).

As an oath, attested from late 14c. For Jesus H. Christ (1924), see I.H.S. First record of Jesus freak is from 1970. Jesu, common in Middle English, is from the Old French objective case.
jet (n.1): "stream of water," 1690s, from French jet, from jeter (see jet (v.)). Sense of "spout or nozzle for emitting water, gas, fuel, etc." is from 1825. Hence jet propulsion (1867) and the noun meaning "airplane driven by jet propulsion" (1944, from jet engine, 1943). The first one to be in service was the German Messerschmitt Me 262. Jet stream is from 1947. Jet set first attested 1951, slightly before jet commuter plane flights began. Jet age is attested from 1952.
jet (v.): early 15c., "to prance, strut, swagger," from Middle French jeter "to throw, thrust," from Late Latin iectare, abstracted from deiectare, proiectare, etc., in place of Latin iactare "toss about," frequentative of iacere "to throw, cast," from PIE root *ye- "to do" (cf. Greek iemi, ienai "to send, throw;" Hittite ijami "I make"). Meaning "to sprout or spurt forth" is from 1690s. Related: Jetted; jetting.
jet (n.2): "deep black lignite," mid-14c., from Anglo-French geet, Old French jaiet "jet, lignite" (12c.), from Latin gagates, from Greek gagates lithos "stone of Gages," town and river in Lycia. As "a deep black color," also as an adjective, attested from mid-15c.
jet lag (n.): also jetlag, 1966, from jet (n.2) + lag (n.). Also known in early days as time zone syndrome.
jete (n.): ballet step, 1830, from French (pas) jeté, from past participle of jeter "to throw" (see jet (v.)).
Jethro: masc. proper name, biblical father-in-law of Moses, from Hebrew Yithro, collateral form of Yether, literally "abundance," from base y-t-r "to be left over, to remain."
jetsam (n.): 1560s, jottsome "act of throwing goods overboard to lighten a ship," alteration and contraction of Middle English jetteson, from Anglo-French getteson, Old French getaison "a throwing" (see jettison). Intermediate forms were jetson, jetsome; the form perhaps was deformed by influence of flotsam. From 1590s as "goods thrown overboard;" figurative use by 1861. For distinction of meaning, see flotsam.
jettison (v.): 1848, from jettison (n.) "act of throwing overboard" to lighten a ship. This noun was an 18c. Marine Insurance writers' restoration of the earlier form and original sense of the 15c. word that had become jetsam, probably because jetsam had taken on a sense of "things cast overboard" and an unambiguous word was needed for "act of throwing overboard."

Middle English jetteson (n.) "act of throwing overboard" is from Anglo-French getteson, from Old French getaison "act of throwing (goods overboard)," especially to lighten a ship in distress, from Late Latin iactionem (nominative iactatio) "act of throwing," noun of action from past participle stem of iectare "toss about" (see jet (v.)). Related: Jettisoned.
jetty (n.): early 15c., from Old French jetee "a jetty, a projecting part of a building," also "a throw," noun use of fem. past participle of jeter "to throw" (see jet (v.)). Notion is of a structure "thrown out" past what surrounds it.