n. 自由飞轮

vi. 随心所欲, 凭惯性滑行

Freewheel \Free"wheel`\, n. (Mach.)
A clutch fitted in the rear hub of a cycle, which engages the
rear sprocket with the rear wheel when the pedals are rotated
forwards, but permits the rear wheel to run on free from the
rear sprocket when the pedals are stopped or rotated
backwards. Freewheelcycles are usually fitted with hub brakes
or rim brakes, operated by back pedaling.
[Webster 1913 Suppl.]


Freewheel \Free"wheel`\, v. i.
1.
(a) Of a freewheel cycle, to run on while the pedals are
held still.
(b) Of a person, to ride a cycle of this manner; to coast
in a vehicle having a freewheel. To ride a freewheel
cycle. [WordNet sense 2]
[Webster 1913 Suppl.]

2. (Mach.) To operate like a freewheel, so that one part
moves freely over another which normally moves with it; --
said of a clutch.
[Webster 1913 Suppl.]

3. to act without controls, external or internal; to live
freely, independently, and without concern; -- of people.
[WordNet sense 1]
[PJC]