ec-

word-forming element, in English meaning usually "out of, from," but also "upwards, completely, deprive of, without," and "former;" from Latin ex "out of, from within; from which time, since; according to; in regard to," from PIE *eghs "out" (source also of Gaulish ex-, Old Irish ess-, Old Church Slavonic izu, Russian iz). In some cases also from Greek cognate ex, ek. PIE *eghs had comparative form *eks-tero and superlative *eks-t(e)r-emo-. Often reduced to e- before -b-, -d-, -g-, consonantal -i-, -l-, -m-, -n-, -v- (as in elude, emerge, evaporate, etc.).

c. 1300, from Old French eclipse "eclipse, darkness" (12c.), from Latin eclipsis, from Greek ekleipsis "an eclipse; an abandonment," literally "a failing, forsaking," from ekleipein "to forsake a usual place, fail to appear, be eclipsed," from ek "out" (see ex-) + leipein "to leave" (from PIE root *leikw- "to leave").

late 14c., extasie "elation," from Old French estaise "ecstasy, rapture," from Late Latin extasis, from Greek ekstasis "entrancement, astonishment, insanity; any displacement or removal from the proper place," 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, make or be firm."

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. Formerly also spelled ecstasie, extacy, extasy, etc. Attempts to coin a verb to go with it include ecstasy (1620s), ecstatize (1650s), ecstasiate (1823), ecstasize (1830).