Definition of "freewheel"

freewheel

noun
plural freewheels
1. a device in a transmission that disengages the driveshaft from the driven shaft when the driven shaft rotates faster than the driveshaft.
verb
third-person singular simple present freewheels, present participle freewheeling, simple past and past participle freewheeled
1. (of a gear) To continue spinning after disengagement.
2. (of a cyclist) To ride a bicycle without pedalling, e.g. downhill.
  Quotations
  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. (of a motorist) To operate a motor vehicle which is coasting without power, e.g. downhill.
4. (by extension) To operate free from constraints.