Thigh, a term applied to that part of the human body, which is situated between the pelvis, or bason, and the knee; thus forming the upper portion of the lower extremity. The principal affections to which this limb is liable, being FRACTURE, Dislocation, and sciatica, it will be unnecessary to enter into any farther discussion on these heads ; as they have been already treated of, vol. ii. p. 331; vol. iii. pp. 136, and 488.