diarthrosis

n., pl., -ses (-sēz).
Any of several types of bone articulation permitting free motion in a joint, as that of the shoulder or hip.

[Greek diarthrōsis, from diarthroun, to articulate : dia-, between; see dia- + arthroun, to fasten by a joint (from arthron, joint).]

diarthrodial di'ar·thro'di·al (-dē-əl) adj.

Pl. diarthroses [Gr.] a specialized form of articulation in which there is more or less free movement, the union of the bony elements being surrounded by an articular capsule enclosing a cavity lined by synovial membrane; called also synovial joint.

• d. rotatoria — a joint characterized by mobility in a rotary direction.