The term PART JOINT is a type of woodworking joint that consists of two parts, a TENON and a mortise. The TENON is a projection on the end of a piece of wood that fits into a mortise, which is a cavity cut into another piece of wood. The TENON is usually made up of two parts, a shoulder and a tongue, and is secured in the mortise with glue or dowels. This type of joint is strong and durable, making it ideal for furniture construction.