Operative
来自Big Physics
late Middle English: from late Latin operativus, from Latin operat- ‘done by labour’, from the verb operari (see operate).
wiktionary
From Middle French operatif (modern French opératif).
etymonline
operative (adj.)
late 15c., operatif, "active, working," from Old French operatif (14c.) and directly from Medieval Latin operativus "creative, formative," from operat-, past-participle stem of operari (see operation). Meaning "producing the intended effect" is from 1590s.
operative (n.)
1809, "worker, operator, artisan," from operative (adj.); sense of "secret agent, spy" is attested from 1930, probably from its use by the Pinkerton Detective Agency as a title for their private detectives (1905) to avoid the term detective.
