/spav"in/ , n. Vet. Pathol.
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.
[ 1400-50; late ME spaveyne e ) spavain, esparvain swelling ]