| 1. | a disease of the hock joint of horses in which enlargement occurs because of collected fluids (bog spavin), bony growth (bone spavin), or distention of the veins (blood spavin). |
| 2. | an excrescence or enlargement so formed. |

| bone spavin n. A condition in horses caused by the deposition of new bone in the hock joint and sometimes producing lameness. |