1. A cartilaginous neoplasm arising as an overgrowth from normally situated cartilage, as a mass protruding from the articular surface of a bone, in contrast to enchondroma.
2. An enchondroma which has burst through the shaft of a bone and become pedunculated.
[G. ek, from, + chondros, cartilage, + -oma, tumor]
a hyperplastic growth of cartilaginous tissue on the surface of a cartilage or projecting under the periosteum of a bone.