Is it ensure, insure, or assure?
c.1400, "devised method of organization," from Old French invencion (13c.) and directly from Latin inventionem (nominative inventio) "faculty of invention; a finding, discovery," noun of action from past participle stem of invenire "devise, discover, find," from in- "in, on" (see in- (2)) + venire "to come" (see venue).
Meaning "finding or discovering of something" is early 15c. in English; sense of "thing invented" is first recorded 1510s. Etymological sense preserved in Invention of the Cross, Church festival (May 3) celebrating the reputed finding of the Cross of the Crucifixion by Helena, mother of Constantine, in 326 C.E.
in music, any of a number of markedly dissimilar compositional forms dating from the 16th century to the present. While its exact meaning has never been defined, the term has often been affixed to compositions of a novel, progressive character-i.e., compositions that do not fit established categories. The earliest-known use of the term in Premier livre des inventions musicales (1555; "First Book of Musical Inventions") by the Frenchman Clement Janequin clearly alludes to the composer's highly original programmatic chansons-secular French part-songs containing extramusical allusions (e.g., imitations of battle sounds and birdcalls). Similarly capricious or novel effects occur in John Dowland's Invention for Two to Play upon One Lute (1597); Lodovico da Viadana's Cento concerti ecclesiasticiNova inventione (1602; "One-Hundred Ecclesiastical ConcertiNew Invention"), the first sacred collection to require a basso continuo; and Antonio Vivaldi's Il cimento dell'armonia e dell'invenzione, Opus 8 (1720; "The Contest Between Harmony and Invention"), which contains, among others, a number of programmatic concerti