enarthrosis

from WordNet (r) 3.0 (2006)

enarthrosis
    n 1: a freely moving joint in which a sphere on the head of one
         bone fits into a rounded cavity in the other bone [syn:
         {ball-and-socket joint}, {spheroid joint}, {cotyloid
         joint}, {enarthrodial joint}, {enarthrosis}, {articulatio
         spheroidea}]

from The Collaborative International Dictionary of English v.0.48

Enarthrosis \En`ar*thro"sis\, n. [NL., fr. Gr. ?, fr. ? jointed;
   ? in + ? joint.] (Anat.)
   A ball and socket joint, or the kind of articulation
   represented by such a joint. See {Articulation}.
   [1913 Webster]

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