ecliptic (n.) Look up ecliptic at Dictionary.com
late 14c., "the circle in the sky followed by the Sun," from Medieval Latin ecliptica, from Late Latin (linea) ecliptica, from Greek ekliptikos "of an eclipse" (see eclipse (n.)). So called because eclipses happen only when the Moon is near the line. Related: Ecliptical.
eclogue (n.) Look up eclogue at Dictionary.com
"short poem," especially a pastoral dialogue, mid-15c., from Latin ecloga "selection, short poem, eclogue," from Greek ekloge "selection," from eklegein "to select" (see eclectic).
eco- Look up eco- at Dictionary.com
word-forming element referring to the environment and man's relation to it, abstracted from ecology, ecological; attested from 1969.
ecocentric (adj.) Look up ecocentric at Dictionary.com
also eco-centric, by 1975, from eco- + -centric.
ecofriendly (adj.) Look up ecofriendly at Dictionary.com
also eco-friendly, by 1993, from eco- + friendly.
ecological (adj.) Look up ecological at Dictionary.com
1899, see ecology + -ical. Related: Ecologically.
ecologist (n.) Look up ecologist at Dictionary.com
1893, see ecology + -ist.
ecology (n.) Look up ecology at Dictionary.com
1873, "branch of science dealing with the relationship of living things to their environments, coined by German zoologist Ernst Haeckel (1834-1919) as Okologie, from Greek oikos "house, dwelling place, habitation" (see villa) + -logia "study of" (see -logy). In use with reference to anti-pollution activities from 1960s.
econometric (adj.) Look up econometric at Dictionary.com
1933, from comb. form of economy + -metric.
economic (adj.) Look up economic at Dictionary.com
1590s, "pertaining to management of a household," perhaps shortened from economical or from French économique or directly from Latin oeconomicus "of domestic economy," from Greek oikonomikos "practiced in the management of a household or family," hence, "frugal, thrifty," from oikonomia (see economy (n.)). Meaning "relating to the science of economics" is from 1835 and now is the main sense, economical retaining the older one of "characterized by thrift."
economical (adj.) Look up economical at Dictionary.com
1570s, "pertaining to household management; from economic + -al (1). Meaning "pertaining to political economy" is from 1781; that of "thrifty" is from 1780. Related: Economically.
economics (n.) Look up economics at Dictionary.com
1580s, "art of managing a household," perhaps from French économique (see economic); also see -ics. Meaning "science of wealth" is from 1792.
economist (n.) Look up economist at Dictionary.com
1580s, "household manager," from Middle French économiste; meaning "student of political economy" is from 1804; see economy + -ist.
economize (v.) Look up economize at Dictionary.com
1640s, "to govern a household," from economy + -ize. Meaning "to spend less" is from 1790. Related: Economized; economizing; economization; economizer.
economy (n.) Look up economy at Dictionary.com
1530s, "household management," from Latin oeconomia, from Greek oikonomia "household management, thrift," from oikonomos "manager, steward," from oikos "house" (cognate with Latin vicus "district," vicinus "near;" Old English wic "dwelling, village;" see villa) + nomos "managing," from nemein "manage" (see numismatic). The sense of "wealth and resources of a country" (short for political economy) is from 1650s.
economy (adj.) Look up economy at Dictionary.com
1821 as a term in advertising, at first meant simply "cheaper," then "bigger and thus cheaper per unit or amount" (1950). See economy (n.).
ecosphere (n.) Look up ecosphere at Dictionary.com
1953, the region around a star where conditions allow life-bearing planets to exist; see eco- + sphere. Apparently coined by German-born U.S. physician and space medicine pioneer Hubertus Strughold (1898-1986).
ecosystem (n.) Look up ecosystem at Dictionary.com
1935; see eco- + system. Perhaps coined by English ecologist Sir Arthur George Tansley (1871-1955).
ecotourism (n.) Look up ecotourism at Dictionary.com
by 1989, from eco- + tourism. Related: Ecotourist.
ecru (adj.) Look up ecru at Dictionary.com
1869, from French écru "raw, unbleached," from Old French escru "raw, crude, rough" (13c.), from es- "thoroughly" (see ex-) + Latin crudus "raw" (see crude).
ecstasy (n.) Look up ecstasy at Dictionary.com
late 14c., "in a frenzy or stupor, fearful, excited," from Old French estaise "ecstasy, rapture," from Late Latin extasis, from Greek ekstasis "entrancement, astonishment; any displacement," in New Testament "a trance," from existanai "displace, put out of place," also "drive out of one's mind" (existanai phrenon), from ek "out" (see ex-) + histanai "to place, cause to stand," from PIE root *sta- "to stand" (see stet).

Used by 17c. mystical writers for "a state of rapture that stupefied the body while the soul contemplated divine things," which probably helped the meaning shift to "exalted state of good feeling" (1610s). Slang use for the drug 3,4-methylendioxymethamphetamine dates from 1985.
ecstatic (adj.) Look up ecstatic at Dictionary.com
1590s, "mystically absorbed, stupefied," from Greek ekstatikos "unstable," from ekstasis (see ecstasy). Meaning "characterized by intense emotions" is from 1660s, now usually pleasurable ones, but not originally always so. Related: Ecstatical; ecstatically.
ecto- Look up ecto- at Dictionary.com
word-forming element generally meaning "outside, external," before vowels ect-, comb. form of Greek ektos "outside" (adv.), used to form scientific compounds in Greek; related to Greek ek, ex "out," from PIE *eghs- (see ex-).
ectoderm (n.) Look up ectoderm at Dictionary.com
1853, from ecto- + -derm. Coined by Prussian embryologist Robert Remak (1815-1865).
ectomorph (n.) Look up ectomorph at Dictionary.com
1940, coined by Sheldon from ecto- + Greek morphe (see morphine). Related: Ectomorphic.
ectopic (adj.) Look up ectopic at Dictionary.com
1864 in reference to pregnancy, from ectopia (1847), coined in Modern Latin from Greek ektopos "away from a place," from ek- "out" (see ex-) + topos "place" (see topos).
ectoplasm (n.) Look up ectoplasm at Dictionary.com
1883, of amoebas, 1901, of spirits, from ecto- + -plasm.
ecu (n.) Look up ecu at Dictionary.com
old French silver coin, 1704, from French écu, from Old French escu (12c.) "shield, coat of arms," also the name of a coin, from Latin scutum "shield" (see hide (n.1)). First issued by Louis IX (1226-1270); so called because the shield of France was imprinted on them.
Ecuador Look up Ecuador at Dictionary.com
from the Spanish form of equator (which runs through it). Before 1830 the region bore the name of its chief city, Quito, which is from the name of a now-extinct native people, of unknown meaning. Related: Ecuadorian; Ecuadorean.
ecumenical (adj.) Look up ecumenical at Dictionary.com
late 16c., "representing the entire (Christian) world," formed in English as an ecclesiastical word, from Late Latin oecumenicus "general, universal," from Greek oikoumenikos, from he oikoumene ge "the inhabited world (as known to the ancient Greeks); the Greeks and their neighbors considered as developed human society," from oikoumenos, present passive participle of oikein "inhabit," from oikos "house, habitation" (see villa).
ecumenism (n.) Look up ecumenism at Dictionary.com
1937, from ecumen- (see ecumenical) + -ism.
eczema (n.) Look up eczema at Dictionary.com
1753, from Greek ekzema, literally "something thrown out by heat," from ekzein "to boil out," from ek "out" (see ex-) + zema "boiling," from zein "to boil," from PIE root *yes- "to boil, foam, bubble" (see yeast). Said to have been the name given by ancient physicians to "any fiery pustule on the skin."
edacious (adj.) Look up edacious at Dictionary.com
1736, from Latin edaci-, stem of edax "voracious, gluttonous," from edere "to eat" (see edible) + -ous. Related: Edacity (1620s).
Edam Look up Edam at Dictionary.com
1836, cheese named for Edam, village in Holland where it was originally made. The place name is literally "the dam on the River Ye," which flows into the Ijsselmeer there, and the river name is literally "river" (see ea).
Edda (n.) Look up Edda at Dictionary.com
1771, by some identified with the name of the old woman in the Old Norse poem "Rigsþul," by others derived from Old Norse oðr "spirit, mind, passion, song, poetry" (cognate with Old Irish faith "poet," Welsh gwawd "poem," Old English woþ "sound, melody, song," Latin vates "seer, soothsayer;" see wood (adj.)).

It is the name given to two Icelandic books, the first a miscellany of poetry, mythology, and grammar by Snorri Sturluson (d.1241), since 1642 called the Younger or Prose Edda; and a c.1200 collection of ancient Germanic poetry and religious tales, called the Elder or Poetic Edda.
eddy (n.) Look up eddy at Dictionary.com
mid-15c., Scottish ydy, possibly from Old Norse iða "whirlpool," from Proto-Germanic *ith- "a second time, again," which is related to the common Old English prefix ed- "again, backwards; repetition, turning" (forming such words as edðingung "reconciliation," edgift "restitution," edniwian "to renew, restore," edhwierfan "to retrace one's steps," edgeong "to become young again"). Compare Old English edwielle "eddy, vortex, whirlpool." The prefix is cognate with Latin et, Old High German et-, Gothic "and, but, however." Related: Eddies.
eddy (v.) Look up eddy at Dictionary.com
1810, from eddy (n.). Related: Eddied; eddying.
edelweiss (n.) Look up edelweiss at Dictionary.com
1862, from German Edelweiß, literally "noble white," from Old High German edili "noble" (see atheling) + German weiss "white" (see white).
edema (n.) Look up edema at Dictionary.com
c.1400, from medical Latin, from Greek oidema (genitive oidematos) "a swelling tumor," from oidein "to swell," from oidos "tumor, swelling," from PIE *oid- "to swell" (cognates: Latin aemidus "swelling," Armenian aitumn "a swelling," Old Norse eista "testicle," Old English attor "poison" (that which makes the body swell), and the first element in Oedipus).
Eden (n.) Look up Eden at Dictionary.com
early 13c., "delightful place," figurative use of the place described in Genesis, usually referred to Hebrew edhen "pleasure, delight," but perhaps from Ugaritic base 'dn and meaning "a place that is well-watered throughout" (see also Aden).
Edgar Look up Edgar at Dictionary.com
masc. proper name, from Old English Ead-gar, literally "prosperity-spear," from ead "prosperity" + gar (see gar).
edge (n.) Look up edge at Dictionary.com
Old English ecg "corner, edge, point," also "sword" (also found in ecgplega, literally "edge play," ecghete, literally "edge hate," both used poetically for "battle"), from Proto-Germanic *agjo (cognates: Old Frisian egg "edge;" Old Saxon eggia "point, edge;" Middle Dutch egghe, Dutch eg; Old Norse egg, see egg (v.); Old High German ecka, German Eck "corner"), from PIE root *ak- "sharp, pointed" (cognates: Sanskrit asrih "edge," Latin acies, Greek akis "point;" see acrid).

Spelling development of Old English -cg to Middle English -gg to Modern English -dge represents a widespread shift in pronunciation. To get the edge on (someone) is U.S. colloquial, first recorded 1911. Edge city is from Joel Garreau's 1992 book of that name. Razor's edge as a perilous narrow path translates Greek epi xyrou akmes. To have (one's) teeth on edge is from late 14c., though "It is not quite clear what is the precise notion originally expressed in this phrase" [OED].
edge (v.) Look up edge at Dictionary.com
late 13c., "to give an edge to" (implied in past participle egged), from edge (n.). Meaning "to move edgeways (with the edge toward the spectator), advance slowly" is from 1620s, originally nautical. Meaning "to defeat by a narrow margin" is from 1953. The meaning "urge on, incite" (16c.) often must be a mistake for egg (v.). Related: Edged; edging.
edgeways (adv.) Look up edgeways at Dictionary.com
also edge-ways, 1560s, from edge (n.) + way (n.). First attested form of the word is edgewaie; the adverbial genitive -s appears by 1640s. Edgewise (1715) appears to be a variant, based on otherwise, etc. See edge (v.).
As if it were possible for any of us to slide in a word edgewise! [Mary Mitford, "Our Village," 1824].
To edge in a word in this sense is from 1680s.
edgewise Look up edgewise at Dictionary.com
see edgeways.
edging (n.) Look up edging at Dictionary.com
1570s, "the putting of a border," verbal noun from edge (v.). Meaning "a border" is from 1660s; that of "the trimming of lawn edges" is from 1858.
edgy (adj.) Look up edgy at Dictionary.com
"having sharp edges," 1755, from edge (n.) + -y (2). Meaning "tense and irritable" is attested by 1837, perhaps from notion of being on the edge, at the point of doing something irrational (a figurative use attested from c.1600).
edible (adj.) Look up edible at Dictionary.com
1590s, from Late Latin edibilis "eatable," from Latin edere "to eat," from PIE root *ed- "to eat" (cognates: Sanskrit admi "I eat;" Greek edo "I eat;" Lithuanian edu "I eat;" Hittite edmi "I eat," adanna "food;" Old Irish ithim "I eat;" Gothic itan, Old Swedish and Old English etan, Old High German essan "to eat;" Avestan ad- "to eat;" Armenian utem "I eat;" Old Church Slavonic jasti "to eat," Russian jest "to eat").
edict (n.) Look up edict at Dictionary.com
late 15c., edycte; earlier edit, late 13c., "proclamation having the force of law," from Old French edit, from Latin edictum "proclamation, ordinance, edict," neuter past participle of edicere "publish, proclaim," from e- "out" (see ex-) + dicere "to say" (see diction).
edification (n.) Look up edification at Dictionary.com
mid-14c., in religious use, "building up of the soul," from Old French edification and directly from Latin aedificationem (nominative aedificatio) "construction, building," in Late Latin "spiritual improvement," from past participle stem of aedificare (see edifice). Religious use is as translation of Greek oikodome in I Cor. xiv. Meaning "mental improvement" is 1650s. Literal sense of "building" is rare in English.