ball-and-socket joint
/ˈbɔːl ɒv ˈkleɪ/
n
English · ball-and-socket joint中文 · 球窝关节Español · articulación esferoideaFrançais · articulation sphérique
意味：Allows movement along three axes, such as in the elbow: flexion and extension, rotation, and adduction (arm drawing near the trunk) and abduction (arm drawing away from the trunk).