detent

de·tent  (d-tnt)

n.

A catch or lever that locks the movement of one part of a mechanism.

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[French détente, a loosening, from Old French destente, from feminine past participle of destendre, to release : des-, de- + tendre, to stretch (from Latin tendere; see ten- in Indo-European roots).]

Thesaurus

Noun

1.

detent - a hinged catch that fits into a notch of a ratchet to move a wheel forward or prevent it from moving backward pawl, click, dog catch, stop - a restraint that checks the motion of something; "he used a book as a stop to hold the door open" rachet, ratch, ratchet - mechanical device consisting of a toothed wheel or rack engaged with a pawl that permits it to move in only one direction