A dado is most commonly a woodworking term for a three-sided slot or trench cut across the grain of a board, used to accept and support another piece such as a shelf in a cabinet. This creates a strong joint because the supported piece sits in the channel rather than just being fastened to the surface.
Other meanings
In architecture and interior design, a dado is the lower portion of an interior wall, typically between the baseboard (skirting) and a horizontal trim piece called a dado rail, often finished or decorated differently from the upper wall. Historically, the word also referred to the middle block-like section of a pedestal in classical architecture.
