Define tongue and groove. tongue and groove synonyms, tongue and groove pronunciation, tongue and groove translation, English dictionary definition of tongue and groove. n. A joint made by fitting a tongue on the edge of a board into a matching groove on
tongue-and-groove n (Building) a.the technique of making a joint between two boards by means of a tongue along the edge of one board that fits into a groove along the edge of the other board b.(as modifier):a tongue-and-groove joint. ...