Word Study
synarthrosis
CIDE DICTIONARY
synarthrosis, n. [NL., fr. Gr. a being jointed together, fr. to link or joint together; sy`n with + a joint.].
Immovable articulation by close union, as in sutures. It sometimes includes symphysial articulations also. See the Note under Articulation, n. , 1. [1913 Webster]
OXFORD DICTIONARY
synarthrosis, n. (pl. synarthroses) Anat. an immovably fixed bone-joint, e.g. the sutures of the skull.
Etymology
SYN- + Gk arthrosis jointing f. arthron joint
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