A wood rabbet is a recess or groove cut into the edge of a piece of machinable wood. When viewed in a cross-section, a rabbet is two-sided and open to the edge or end of the surface into which it is cut.
An example of the use of a rabbet is in shiplap planking, very popular in truck and trailer decking applications. A rabbet can be used to form a joint with another piece of wood (often containing a dado).