- operative (adj.)
- 1598, "producing the intended effect," from L.L. operativus "creative, formative," from operatus, pp. of operari (see operation). Weakened sense of "significant, important" is from 1955. The noun meaning "worker, operator" is from 1809; sense of "secret agent, spy" is first attested 1930, probably from its use by the Pinkerton Detective Agency as a title for their private detectives (1905).