1. fusion of bones: the fusion of bones of a joint, often as a result of disease or injury, or intentionally through surgery
2. stiffness of joint bones: stiffness or immobility in a joint caused by bones fusing as a result of disease or injury, or intentionally through surgery
[Early 18th century. Via modern Latin< Greek agkulōsis "stiffening of the joints" < agkuloun "bend" < agkulos "bent"]
