spay definition by Webster's New World
Origin: Middle English spayen, aphetic ; from Anglo-French espeier ; from Old French espeer, to cut with a sword ; from espee, sword ; from Classical Latin spatha: see spade
spay definition by American Heritage Dictionary
transitive verb spayed, spay·ing, spays
Origin: Middle English spaien, from Anglo-Norman espeier, to cut with a sword, from espee, sword, from Latin spatha; see spathe.
spay - Medical Definition