Wiktionary
abarthrosis
n. A form of articulation that allows considerable change in position and spatial relationship between the articulated parts, and which bones move freely upon one another; diarthrosis.(reference-book editor =Gove, Philip Babcock title = Webster's Third International Dictionary of the English Language Unabridged origyear = 1909 year =1976 publisher =G. & C. Merriam Co. location = Springfield, MA isbn =0-87779-101-5)