- incentive (n.) early 15c., from L.L. incentivum, noun use of neuter of Latin adjective incentivus "setting the tune" (in L.L. "inciting"), from pp. stem of incinere "strike up," from in- "in, into" (see IN- (Cf. in-) (2)) + canere "sing" (see CHANT (Cf. chant)). Sense influenced by association with incendere "to kindle." The adjective use, in reference to a system of rewards meant to encourage harder work, first attested 1943 in jargon of the U.S. war economy; as a noun, in this sense, from 1948.
Etymology dictionary. 2014.