Source : Webster's Revised Unabridged Dictionary (1913)

Abarticulation \Ab`ar*tic`u*la"tion\
   (acr/b`[aum]r*t[i^]k`[-u]*l[=a]"sh[u^]n), n. [L. ab + E.
   articulation : cf. F. abarticulation. See {Article}.] (Anat.)
   Articulation, usually that kind of articulation which admits
   of free motion in the joint; diarthrosis. --Coxe.

Source : WordNet®

abarticulation
     n : dislocation of a joint