Search Result for "tongue and groove joint":
Wordnet 3.0

NOUN (1)

1. a mortise joint made by fitting a projection on the edge of one board into a matching groove on another board; 



WordNet (r) 3.0 (2006):

tongue and groove joint
    n 1: a mortise joint made by fitting a projection on the edge of
         one board into a matching groove on another board