semicircular canal(redirected from Posterior semicircular duct)
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Related to Posterior semicircular duct: anterior semicircular canal
Any of three tubular and looped structures of the inner ear, together functioning in maintenance of the sense of balance in the body.
Etymology: L, semi-, half, circulare, to go around, canalis, channel
any of three bony fluid-filled loops in the osseous labyrinth of the internal ear, associated with the sense of balance. The posterior, superior, and lateral canals, all about 0.8 mm in diameter and perpendicular to each other, open into the cochlea. The posterior canal is the longest.
One of the three perpendicular tubular hollows, each forming two-thirds of a circle, that extend from the vestibule of the labyrinth in the inner ear. The semicircular canals are the bony shells that contain the similarly shaped semicircular ducts, membranous sensory organs that detect the angular acceleration and the orientation of the head.
See also: canal