Online Etymology Dictionary

Enfield (n.): type of rifle, 1854, named for government works in Enfield, Middlesex, England, where it was manufactured.
enfilade (n.): 1706, a string of things in a straight line, from French enfilade, from Old French enfiler (13c.) "to thread (a needle) on a string; pierce from end to end," from en- "put on" (see en- (1)) + fil "thread" (see file (v.1)). Used of rows of apartments and lines of trees before military sense came to predominate: "a firing with a straight passage down ranks of men, channels in fortifications, etc." (1796). As a verb from 1706 in the military sense, "rake with shot through the full length." Related: Enfiladed; enfilading. The Old French verb was borrowed in Middle English as enfile "to put (something) on a thread or string."
enflame (v.): mid-14c.; see inflame. Related: Enflamed; enflaming.
enfold (v.): also infold, early 15c., from en- (1) "make, put in" + fold (n.). Related: Enfolded; enfolding.
enforce (v.): mid-14c., "to drive by physical force; to try, attempt, strive; to fortify, strengthen a place;" late 14c. as "exert force, compel; make stronger, reinforce; strengthen an argument; grow stronger, become violent," from Old French enforcier "strengthen, reinforce; use force (on), offer violence (to); oppress; violate, rape" (12c.) or a native formation from en- (1) "make, put in" + force (n.). Meaning "compel obedience to (a law, etc.) is from 1640s. Related: Enforced; enforcing.
enforceable (adj.): 1580s, from enforce + -able. Related: Enforceability (1851).
enforcement (n.): late 15c., "constraint, compulsion," from Old French enforcement "strengthening, fortification; rape; compulsion, coercion;" from enforcier; see enforce + -ment. Meaning "compelling of obedience to a law, etc." is from 1680s.
enforcer (n.): 1570s, "one who compels, constrains, or urges," agent noun from enforce. Underworld slang meaning "violent intimidator" is from 1934, U.S. underworld slang.
enfranchise (v.): early 15c., "grant (someone) the status or privilege of citizenship, admit to membership in a town," from Old French enfranchiss-, present participle stem of enfranchir "to set or make free; grant a franchise to;" from en- "make, put in" (see en- (1)) + franc "free" (see franchise (n.)). Generally with reference to voting privileges after c. 1700. Related: Enfranchised; enfranchisement.
engage (v.): early 15c., "to pledge" (something, as security for payment), from Old French engagier "bind (by promise or oath), pledge; pawn" (12c.), from phrase en gage "under pledge," from en "in" (see en- (1)) + gage "pledge," through Frankish from Proto-Germanic *wadiare "pledge" (see wed). It shows the common evolution of Germanic -w- to central French -g- (see gu-). Meaning "attract and occupy the attention of" is from 1640s; that of "employ, secure for aid, employment or use" is from 1640s, from notion of "binding as by a pledge;" meaning "enter into combat or contest with" is from 1640s. Specific sense of "promise to marry" is 1610s (implied in engaged). Machinery sense is from 1884. Also from the French word are German engagiren, Dutch engageren, Danish engagere.
engaged (adj.): "affianced, betrothed," 1610s, past participle adjective from engage. Of telephone lines from 1891.
engagement (n.): 1620s, "formal promise," from engage + -ment. Meaning "a battle or fight between armies or fleets" is from 1660s; sense of "state of having entered into a promise of marriage" is from 1742; meaning "appointment" is from 1806. Engagement ring attested by 1863.
engaging (adj.): "interesting, winning, attractive," 1670s, present participle adjective from engage. Related: Engagingly.
engender (v.): early 14c., "beget, procreate," from Old French engendrer (12c.) "give birth to, beget, bear; cause, bring about," from Latin ingenerare "to implant, engender, produce," from in- "in" (see in- (2)) + generare "beget, create" (see generation). With euphonious -d- in French. Also from early 14c. engendered was used in a theological sense, with reference to Jesus, "derived (from God)." Meaning "cause, produce" is mid-14c. Related: Engendering.
engine (n.): c. 1300, "mechanical device," especially one used in war; "manner of construction," also "skill, craft, innate ability; deceitfulness, trickery," from Old French engin "skill, wit, cleverness," also "trick, deceit, stratagem; war machine" (12c.), from Latin ingenium "inborn qualities, talent" (see ingenious), in Late Latin "a war engine, battering ram" (Tertullian, Isidore of Seville). Sense of "device that converts energy to mechanical power" is 18c.; in 19c. especially of steam engines. Middle English also had ingeny (n.) "gadget, apparatus, device," directly from Latin ingenium.
engineer (n.): mid-14c., enginour, "constructor of military engines," from Old French engigneor "engineer, architect, maker of war-engines; schemer" (12c.), from Late Latin ingeniare (see engine); general sense of "inventor, designer" is recorded from early 15c.; civil sense, in reference to public works, is recorded from c. 1600 but not the common meaning of the word until 19c (hence lingering distinction as civil engineer). Meaning "locomotive driver" is first attested 1832, American English. A "maker of engines" in ancient Greece was a mekhanopoios.
engineer (v.): 1818, "act as an engineer," from engineer (n.). Figurative sense of "arrange, contrive, guide or manage (via ingenuity or tact)" is attested from 1864, originally in a political context. Related: Engineered. Middle English had a verb engine "contrive, construct" (late 14c.), also "seduce, trick, deceive" (c. 1300) and "put to torture."
engineering (n.): 1720, "work done by an engineer," from engineer (n.). As a field of study, attested from 1792. An earlier word was engineership (1640s); engineery was attempted in 1793, but it did not stick.
engird (v.): 1560s, from en- (1) "in" + gird (v.). Related: Engirt; engirded.
England (n.): Old English Engla land, literally "the land of the Angles" (see English (n.1)), used alongside Angelcynn "the English race," which, with other forms, shows Anglo-Saxon persistence in thinking in terms of tribes rather than place. By late Old English times both words had come to be used with a clear sense of place, not people; a Dane, Canute, is first to call himself "King of England." By the 14c. the name was being used in reference to the entire island of Great Britain and to the land of the Celtic Britons before the Anglo-Saxon conquest. The loss of one of the duplicate syllables is a case of haplology.
English (n.1): "the people of England; the speech of England," noun use of Old English adjective Englisc (contrasted to Denisc, Frencisce, etc.), "of or pertaining to the Angles," from Engle (plural) "the Angles," the name of one of the Germanic groups that overran the island 5c., supposedly so-called because Angul, the land they inhabited on the Jutland coast, was shaped like a fish hook (see angle (n.)). The use of the word in Middle English was reinforced by Anglo-French Engleis. Cognates: Dutch Engelsch, German Englisch, Danish Engelsk, French Anglais (Old French Engelsche), Spanish Inglés, Italian Inglese.

Technically "of the Angles," but Englisc also was used from earliest times without distinction for all the Germanic invaders -- Angles, Saxon, Jutes (Bede's gens Anglorum) -- and applied to their group of related languages by Alfred the Great. "The name English for the language is thus older than the name England for the country" [OED]. After 1066, it specifically meant the native population of England (as distinguished from Normans and French occupiers), a distinction which lasted about a generation. But as late as Robert of Gloucester's "Chronicle" (c. 1300) it still could retain a sense of "Anglian" and be distinguished from "Saxon" ("Þe englisse in þe norþ half, þe saxons bi souþe").
... when Scots & others are likely to be within earshot, Britain & British should be inserted as tokens, but no more, of what is really meant [Fowler]
In pronunciation, "En-" has become "In-," perhaps through the frequency of -ing- words and the relative rarity of -e- before -ng- in the modern language. A form Inglis is attested from 14c. and persisted in Scotland and northern England, but the older spelling has stood fast.

Meaning "English language or literature as a subject at school" is from 1889. Old English meaning the Anglo-Saxon language before the Conquest is attested from c. 1200 in an account of the native (as opposed to Latin) month names.
English (n.2): "spin imparted to a ball" (as in billiards), 1860, from French anglé "angled" (see angle (n.)), which is similar to Anglais "English."
English (adj.): Old English, "belonging to the English people;" late 13c., "belonging to England," from English (n.1). The adjective in Old English meant "of or pertaining to the Angles." The adverb Englishly (mid-15c.) is rare.
english (v.): "to translate into English," late 14c., from English (n.1) in the language sense. Related: Englished; englishing.
Englishman: Old English Engliscman, from English (n.1) + man (n.). Related: Englishmen. Englishwoman is from c. 1400. Englander "native of England" is from 1820; in some cases from German Engländer. Englisher is from 1680s. Englishry is from late 13c. in Anglo-French as "state of being English;" from mid-15c. as "the English people or faction."
engorge (v.): 1510s, "fill to excess," from French engorger "to obstruct, block, congest," Old French engorgier "to swallow, devour," from en- (see en- (1)) + gorge "throat" (see gorge (n.)). Probably originally in reference to hawks. Related: Engorged; engorging.
engorgement (n.): 1610s, from engorge + -ment or else from French engorgement.
engraft (v.): 1580s, from en- (1) + graft (n.). Originally figurative. Related: Engrafted; engrafting.
engrain (v.): also ingrain, late 14c., originally "dye (a fabric) red with cochineal," from French phrase en graine, from graine "seed of a plant," also "cochineal" (the source of the dye was thought to be berries), thus "fast-dyed." See grain; also compare kermes. Later associated with grain in the sense of "the fiber of a thing." Used figuratively from 16c. Related: Engrained.
engrave (v.): mid-15c. (implied in ingraved "engraved"), from en- (1) + obsolete verb grave "carve" (see grave (v.)) or from or modeled on French engraver. Related: Engraved; engraven; engraving.
engraver (n.): 1580s, agent noun from engrave.
engraving (n.): c. 1600, "act of cutting designs, etc. on a hard surface," verbal noun from engrave (v.). Meaning "that which is engraved" is from 1610s; meaning "impression taken from an engraved plate" is from 1803.
engross (v.): c. 1400, "to buy up the whole stock of" (in Anglo-French from c. 1300), from Old French en gros "in bulk, in a large quantity, at wholesale," as opposed to en detail. See gross.

Figurative sense of "absorb the whole attention" is first attested 1709. A parallel engross, meaning "to write (something) in large letters," is from Anglo-French engrosser, from Old French en gros "in large (letters)." Related: Engrossed; engrossing.
engulf (v.): 1550s, from en- (1) "make, put in" + gulf (n.) or else from Old French engolfer. Originally of seas, whirlpools, etc.; by 1711 of fire and other mediums. Figurative use from 1590s. Related: Engulfed; engulfing.
enhance (v.): late 13c., anhaunsen "to raise, make higher," from Anglo-French enhauncer, probably from Old French enhaucier "make greater, make higher or louder; fatten, foster; raise in esteem," from Vulgar Latin *inaltiare, from Late Latin inaltare "raise, exalt," from altare "make high," from altus "high" (see old). Meaning "raise in station, wealth, or fame" attested in English from c. 1300. Related: Enhanced; enhancing.

The -h- in Old French supposedly is from influence of Frankish *hoh "high." The -n- perhaps is due to association with Provençal enansar, enanzar "promote, further," from enant "before, rather," from Latin in + ante "before."
enhancement (n.): 1570s, from enhance + -ment.
enharmonic (adj.): c. 1600, in reference to Greek music, from Late Latin enharmonicus, from Greek enharmonikos, from en (see en- (2)) + harmonikos (see harmonic). From 1794 in reference to a modern music note that can be indicated in different ways (G sharp/A flat).
ENIAC: acronym from "electronic numeral integrator and computer," device built 1946 at University of Pennsylvania by John W. Mauchly Jr., J. Presper Eckert Jr., and J.G. Brainerd. It cost $400,000, used 18,000 radio tubes, and was housed in a 30-foot-by-50-foot room.
Enid: fem. proper name, from Middle Welsh eneit, "purity," literally "soul," from PIE *ane-tyo-, suffixed form of root *ane- "to breathe" (see animus).
enigma (n.): 1530s, "statement which conceals a hidden meaning or known thing under obscure words or forms," earlier enigmate (mid-15c.), from Latin aenigma "riddle," from Greek ainigma (plural ainigmata) "a dark saying, riddle," from ainissesthai "speak obscurely, speak in riddles," from ainos "tale, story; saying, proverb;" according to Liddell & Scott, a poetic and Ionic word, of unknown origin. General sense in English of "anything inexplicable to an observer" is from c. 1600.
enigmatic (adj.): 1640s, from Late Latin aenigmaticus, from aenigmat-, stem of aenigma (see enigma). Enigmatical in the same sense is from 1570s. Related: Enigmatically.
enisle (v.): c. 1600, from en- (1) "in, into" + isle (n.).
enjambment (n.): also enjambement, 1837, from French enjambement or from enjamb (c. 1600), from French enjamber "to stride over," from en- (see en- (1)) + jambe "leg" (see jamb).
enjoin (v.): c. 1200, engoinen, "to prescribe, impose" (penance, etc.), from stem of Old French enjoindre (12c.) "impose (on), inflict; subject to; assign (to)," from Latin iniungere "to join, fasten, attach;" figuratively "to inflict, to attack, impose," from in- "on" (see in- (2)) + iungere "to join" (see jugular). Related: Enjoined; enjoining.
enjoy (v.): late 14c., "rejoice, be glad" (intransitive), from stem of Old French enjoir "to give joy, rejoice, take delight in," from en- "make" (see en- (1)) + joir "enjoy," from Latin gaudere "rejoice" (see joy); Sense of "have the use or benefit of" first recorded early 15c. (replacing Old English brucan, for which see brook (v.)).

Transitive meaning "take pleasure in" is mid-15c. In modern use it has a tendency to lose its connection with pleasure: newspaper photo captions say someone enjoys an ice cream cone, etc., when all she is doing is eating it, and Wright's "English Dialect Dictionary" (1900) reports widespread use in north and west England of the phrase to enjoy bad health for one who has ailments. Meaning "have sexual relations with" (a woman) is from 1590s. Related: Enjoyed; enjoys; enjoying. To enjoy oneself "feel pleasure or satisfaction in one's mind" attested by 1708.
enjoyable (adj.): 1640s, "capable of being enjoyed," from enjoy + -able. Meaning "affording pleasure" is from 1744. Related: Enjoyably; enjoyableness.
enjoyment (n.): 1550s, "state of enjoying," from enjoy + -ment. As "that which gives pleasure" from 1732.
enkindle (v.): 1540s (literal), 1580s (figurative), from en- (1) + kindle. Related: Enkindled; enkindling.
enlace (v.): late 14c., "connect, involve, entangle," from Old French enlacer "trap, ensnare, capture," from Late Latin *inlaciare, from in- (see in- (2)) + *lacius, from Latin laqueus "noose" (see lace (n.)). Related: Enlaced; enlacing.
enlarge (v.): mid-14c., "grow fat, increase" (intrans.); c. 1400, "make larger" (trans.), from Old French enlargier "to widen, increase, make larger," from en- "make, put in" (see en- (1)) + large (see large). Meaning "expand in words, speak at large" is from 1650s. There was a Middle English verb large "to extend, increase, make bigger," but it did not survive. Related: Enlarged; enlarging.