[1] : The Collaborative International Dictionary of English v.0.48

detent \detent"\, n. f. d'etente, fr. d'etendre to unbend,
   relax; pref. d'e- l. dis- or de + tendre to stretch. see
   distend. mech.
   that which locks or unlocks a movement; a catch, pawl, or
   dog; especially, in clockwork, the catch which locks and
   unlocks the wheelwork in striking.
   1913 webster
see also:
distend 

[2] : WordNet (r) 2.0

detent
     n : a hinged catch that fits into a notch of a ratchet to move a
         wheel forward or prevent it from moving backward syn: pawl,
          click, dog
see also:
pawl click dog 

Detent >> D Words
Detent, definition of term: Detent
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