technicalTI a hole cut in a piece of wood or stone so that the shaped end of another piece will fit there firmly 榫眼，榫孔 → tenon
Examples from the Corpus
mortise• It had a mortise lock, a simple keyhole and no key.• The seat of the chair is a straight forward mortise and tenon construction apart from two considerations.• Fit a five-lever mortise lock to the back door, or supplement the existing lock with a mortise deadlock.• Replace all old surface-mounted bolts with key-operated mortise security bolts.• Wooden framed windows are best secured with locks resembling small mortise security bolts.• The arm and post are then lined up and the mortise marked off on the arm from the post.
Originmortise
(1300-1400)Old Frenchmortaise, perhaps from Arabicmurtazz“fixed in”