freewheel

plural freewheels · alternative free wheel

1. A device in a transmission that disengages the driveshaft from the driven shaft when the driven shaft rotates faster than the driveshaft.
2. The mode or state of operation thus produced: Synonym of neutral.

present singular third person freewheels · participle present freewheeling · participle past freewheeled · past freewheeled

1. intransitiveengineeringOf a gear, to continue spinning after disengagement.
2. intransitivecyclingOf a cyclist, to ride a bicycle without pedalling, e.g. downhill.

   On her elderly bicycle with the basketwork carrier on the handle-bars, Dorothy free-wheeled down the hill, doing mental arithmetic with three pounds nineteen and fourpence--her entire stock of money until next quarter-day.

   1935, George Orwell, chapter 3, in A Clergyman’s Daughter

3. automotiveOf a motorist, to operate a motor vehicle which is coasting without power, e.g. downhill.

   Silently and gracefully I free-wheeled across the path of three juggernauts, [...] glided across the hard shoulder and came to rest halfway up a grass bank.

   1983, Bill Oddie, Gone Birding, London: Methuen, page 78

4. broadlyfigurativelyTo operate free from constraints.