Loose tenon, also commonly referred to as floating tenon or slip tenon, joinery is versatile.
I’ve used loose tenon joints to construct tables, chairs, post-and-rail casework, a workbench, cabinet doors, even architectural doors.
I may be a power tool kind o’ guy, but nevertheless, I favor traditional joints, those proven through centuries of use. The mortise-and-tenon is one. It has been in use not simply for hundreds of years, but for thousands of years, with examples found in ancient Egyptian furniture.
Instead of cutting a mortise in one part and a tenon on the other, I rout identical mortises in both parts to be joined, and connect them with a fitted strip of wood called a loose tenon. Here are the names of the tenon and mortise parts as well as the basic layout rules.