enarthrosis

[Gr. enarthrosis a kind of jointing when the ball is deep set in the socket: en = in, and arthron =a joint.] Anat .: A particular kind of jointing. [Etym.] It is a highly-developed arthrodia. The convex surface a umes a globular shape, and the concavity is so much deepened as to be cup-like; hence the appellation, ball and socket. The ball is kept in apposition with the socket by means of a capsular ligament, which is sometimes strengthened by acce ory fibers at certain parts that are likely to be much pre ed upon. The best example of enarthrosis is the hip-joint, and next to it the shoulder; in the latter the cavity is but imperfectly developed. This species of joint is capable of motion of all kinds, apposition and circumduction being the most perfect, but rotation limited. (Todd & Bowman: Physiol . Anat . , vol. i., ch. vi., p. 137.) *e-năs'-çent, a. [Lat. enascens , pr. par. of enas cor to spring up: e = ex =out, and nascor =to be born.] Rising, springing forth, being born. *ē-nā-ta-tion, s. [Lat.e= ex =out, and natatio a swimming; nato =to swim.] The act of swimming out; an escape by swimming.