1.The hook with its eye, or the joint, on which a door, gate, lid, etc., turns or swings; a flexible piece, as a strip of leather, which serves as a joint to turn on. "The gate self-opened wide, On golden hinges turning."
2.That on which anything turns or depends; a governing principle; a cardinal point or rule; as, this argument was the hinge on which the question turned.
3.One of the four cardinal points, east, west, north, or south. (R.) "When the moon is in the hinge at East." "Nor slept the winds... but rushed abroad."
Hinge joint. (b)(Mech.) Any joint resembling a hinge, by which two pieces are connected so as to permit relative turning in one plane.
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