slipjoint

slip +‎ joint

slipjoint (plural slipjoints)

1. (chiefly attributive) A type of joint for a folding knife, involving a spring that helps hold the blade open against some pressure but does not lock it open in the sense of any positive engagement by the parts of any lock mechanism; it is thus a nonlocking type of joint.
2. (metonymically) A knife or other tool with such a joint; usually a pocketknife.

   Hypernyms: folding knife, folder, clasp-knife

   Coordinate terms: button lock, frame lock, liner lock, lockback