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immovable joint

[ĭ-mōō′və-bəl]
n.
  1. A union of two bones by fibrous tissue, such as a syndesmosis or gomphosis, in which there is no joint cavity and little motion is possible.fibrous joint synarthrodia synarthrodial joint synarthrosis
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.