How is a "dado joint" defined?

A dado joint is defined as a joint made by cutting a groove across the grain of a board to fit another board. This type of joint is commonly used in woodworking to create strong connections between pieces, particularly when joining shelves into the sides of cabinets or bookcases. By cutting a groove, or dado, the adjoining board can be securely inserted, providing additional surface area for glue and improving the overall strength of the assembly.

This method is particularly advantageous because it allows for the other board to be flush with the surface of the board containing the dado, resulting in a clean and professional appearance. Additionally, dado joints help in distributing the load across the joint, which enhances the durability and stability of the structure.

Other definitions do not capture the uniqueness of the dado joint; for example, drilling a hole through a board or making a joint at the end does not describe how the groove is specifically utilized for joining purposes. Overlapping two boards pertains more to lap joints, which also serve a different structural function than that of a dado joint.