Word Study
Spay
CIDE DICTIONARY
Spay, v. t. [Cf. Armor. spac'hein, spaza to geld, W. dyspaddu to geld, L. spado a eunuch, Gr. .].
To remove or extirpate the ovaries of, as a sow or a bitch; to castrate (a female animal). [1913 Webster]
OXFORD DICTIONARY
Spay, v.tr. sterilize (a female animal) by removing the ovaries.
Etymology
ME f. AF espeier, OF espeer cut with a sword f. espee sword f. L spatha: see SPATHE
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