Simple and strong, the mortise and tenon
joint (also called the mortice and tenon) has been used for millennia by
woodworkers around the world to join two pieces of
wood, most often at an angle close to 90°. Although there are many variations on the theme, the basic idea is that end of one of the members is inserted into a hole cut in the other member. The end of the first member is called the tenon, and it is usually narrowed with respect to the rest of the piece. The hole in the second member is called the mortise. The joint may be glued, pinned, or wedged to lock it in place.
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A system of joinery that fitted a tenon from one piece of wood into a mortise (rectangular hole) on another piece. Usually secured with a round peg.