1. A small rounded head or knob-like projection, especially the rounded prominence at the end of a bone that forms part of a joint.
Usage: anatomy; technical
2. In architecture, a small capital or ornamental head of a column or pilaster.
Usage: architecture; rare

Examples

• The capitellum of the humerus articulates with the radius in the elbow joint.
• Fractures of the capitellum are common in young athletes who throw.
• The radiologist identified damage to the capitellum on the X-ray.
• The capitellum forms the lateral condyle of the distal humerus.
• In classical architecture, the capitellum served as a decorative transition between the shaft and entablature.