/bawl"euhn sok"it/
1. Also called enarthrosis . Anat., Zool. a joint in which the rounded end of one bone fits into a cuplike end of the other bone, allowing for relatively free rotary motion, as at the hip or shoulder.
2. Also called ball joint . a similar joint between rods, links, pipes, etc., consisting of a ball-like termination on one part held within a concave, spherical socket on the other.
[ 1660-70 ]