trochlea

Troch"le*a, n. Etym: [L., a case or sheaf containing one or more pulleys, Gr. Trochilics.] 1. (Mach.) Defn: A pulley. [Obs.] 2. (Anat.) Defn: A pulley, or a structure resembling a pulley; as, the trochlea, or pulleylike end, of the humerus, which articulates with the ulna; or the trochlea, or fibrous ring, in the upper part of the orbit, through which the superior oblique, or trochlear, muscle of the eye passes.

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