osteoclastoma /os′tē·ōklastō″mə/ pl. osteoclastomas, osteoclastomata [Gk, osteon + klasis, breaking, oma, tumor] , a giant cell tumor of the bone that occurs most frequently at the end of a long bone and appears as a mass surrounded by a thin shell of new periosteal bone. The lesion may be malignant and may cause local pain, loss of function, weakness, and pathological fracture. Also called giant cell myeloma, giant cell tumor of bone.
