- clamp-down (n.)
[clamp-down 词源字典]
- also clampdown, 1940 in the figurative sense, from verbal phrase clamp down "use pressure to keep down" (1924). The verbal phrase in the figurative sense is recorded from 1941. See clamp (v.) + down (adv.).[clamp-down etymology, clamp-down origin, 英语词源]