false tongue


spline, false tongue, feather, slip feather, slip tongue

spline, 2 spline, 1 1. A long thin strip of wood or metal which is inserted in a slot formed by two members, each of which is grooved and butted against the other. 2. In a suspended acoustical ceiling, a strip of metal or hard fiber inserted in the slot between adjacent acoustical tiles which butt against each other, forming a concealed mechanical joint.