Word Origin & History
1809, "a work, composition," esp. a musical one," from L. opus "a work, labor, exertion" (cf. It. opera, Fr. oeuvre, Sp. obra), from PIE base *op- (Gmc. *ob-) "to work, produce in abundance," originally of agriculture later extended to religious acts (cf. Skt. apas- "work, religious act;" Avestan hvapah-
"good deed;" O.H.G. uoben "to start work, to practice, to honor;" Ger. üben "to exercise, practice;" Du. oefenen, O.N. æfa, Dan. øve "to exercise, practice;" O.E. æfnan "to perform, work, do," afol "power"). The plural, seldom used, is opera.