free-wheelingn.
中文n. 单向转动
词根词源
free-wheeling (adj.)also freewheeling, 1903, from free wheel (1899, see free (adj.) + wheel (n.)); a bicycle wheel that turns even when not being pedaled, later from the name of a kind of automobile drive system that allowed cars to coast without being slowed by the engine. Figurative sense is from 1911.
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