*synarthrosi*

‖n.; pl. Synarthroses [ NL., fr. Gr. &unr_; a being jointed together, fr. &unr_; to link or joint together; sy`n with + &unr_; a joint. ] (Anat.) Immovable articulation by close union, as in sutures. It sometimes includes symphysial articulations also. See the Note under Articulation, n., 1. [ 1913 Webster ]