hinge joint

A junction of parts allowing a flexure and extension in a certain plane. The parts are usually connected by a pintle or ligature. "First, the head rests immediately upon the uppermost of the vertebræ, and is united to the hinge -joint." - Paley : Natural Theology , ch. viii. hinge-line, hinge-margin, s. Zool. ( of the Mollusca): The margin of a conchiferous shell on which the ligament and teeth are situated. ( S. P. Woodward .)