ratchet

Definitions

Cars & Driving

  • noun a toothed rack or wheel which is engaged by a lever to permit motion in one direction only
  • noun a drive handle with ratchet mechanism that permits the socket to rotate in one direction only, i.e. the ratchet releases in one direction, but catches in the other

Construction

  • A mechanism with a hinged catch, or pawl, that slides over and locks behind sloped teeth on a gear or rod, allowing motion in one direction only.

Origin & History of “ratchet”

Ratchet was originally acquired, in the form rochet, from French rochet. this was a diminutive form descended ultimately from Frankish *rokko ‘spool’, which is related to English rocket. The notion of having teeth, which is central to the idea of a ratchet, therefore appears to be historically secondary; it presumably arose from the addition of ‘teeth’ to a rotating ‘spool’ or ‘spindle’ in a machine. The change from rochet to ratchet, which began in the 18th century, may have been influenced by German ratsch ‘ratchet’.
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