In human anatomy of the arm, the lateral portion of the articular surface of the humerus

Humerus

The humerus is a long bone in the arm or forelimb that runs from the shoulder to the elbow....

 consists of a smooth, rounded eminence, named the capitulum of the humerus.

It articulates with the cupshaped depression on the head of the radius, and is limited to the front and lower part of the bone.

In bird

Bird

Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...

s, where forelimb anatomy has adaptation for flight, its functional if not ontogenetic equivalent is the dorsal condyle of the humerus.