noun, plural: arthrodiae
A synovial joint in which the opposing surfaces glide over each other in movement.
Examples are the intermetacarpal joints and the acromioclavicular joint (between the acromion of the scapula and the clavicle).
Word origin: Greek arthrōdía, equiv. to arthrod(ēs) (meaning jointed)
Related term: arthrodial (adjective)