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rule joint

American  

noun

  1. (in carpentry and joinery) a joint between two hinged pieces, as between the center and end leaves of a table, consisting of a quarter round and fillet fitting against a cove and fillet.

  2. a pivoted joint between two strips of wood placed end to end, as in a carpenter's folding rule.


Etymology

Origin of rule joint

First recorded in 1775–85