misadventure n.

word-forming element of Latin origin (in mischief, miscreant, misadventure, misnomer, etc.), from Old French mes- "bad, badly, wrong, wrongly," from Vulgar Latin *minus-, from Latin minus "less" (from suffixed form of PIE root *mei- (2) "small"), which was not used as a prefix in Latin but in the Romanic languages was affixed to words as a depreciative or negative element. The form in French perhaps was influenced in Old French by *miss-, the Frankish (Germanic) form of mis- (1).

c. 1200, aventure, auenture "that which happens by chance, fortune, luck," from Old French aventure (11c.) "chance, accident, occurrence, event, happening," from Latin adventura (res) "(a thing) about to happen," from fem. of adventurus, future participle of advenire "to come to, reach, arrive at." This is from ad "to" (see ad-) + venire "to come" (from a suffixed form of PIE root *gwa- "to go, come").

The meaning developed through "risk; danger" (a trial of one's chances), c. 1300, and "perilous undertaking" (late 14c.) to "novel or exciting incident, remarkable occurrence in one's life" (1560s).

Earlier it also meant "a wonder, a miracle; accounts of marvelous things" (13c.). The -d- was restored in English 15c.-16c.; in French the attempt to restore it at about the same time was rejected. Venture is a 15c. variant. German Abenteuer is a borrowing of the French word, apparently deformed whimsically by influence of Abend "evening."

*gwā-, also *gwem-, Proto-Indo-European root meaning "to go, come."

It forms all or part of: acrobat; adiabatic; advent; adventitious; adventure; amphisbaena; anabasis; avenue; base (n.) "bottom of anything;" basis; become; circumvent; come; contravene; convene; convenient; convent; conventicle; convention; coven; covenant; diabetes; ecbatic; event; eventual; hyperbaton; hypnobate; intervene; intervenient; intervention; invent; invention; inventory; juggernaut; katabatic; misadventure; parvenu; prevenient; prevent; provenance; provenience; revenant; revenue; souvenir; subvention; supervene; venire; venue; welcome.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit gamati "he goes," Avestan jamaiti "goes," Tocharian kakmu "come," Lithuanian gemu, gimti "to be born," Greek bainein "to go, walk, step," Latin venire "to come," Old English cuman "come, approach," German kommen, Gothic qiman.