trochlea
noun [ C ] anatomy specialized uk/ˈtrɒk.li.ə/ us/ˈtrɑːk.li.ə/ trochleae
（尤指肱骨的）滑车
a long, narrow, hollow space in a surface in the body that a bone or tendon can move against, especially the lower end of the humerus (= the long bone of the upper arm)
the trochlea of the humerus 肱骨滑车