freemartin

Late 17th century. Etymology unknown.

freemartin (plural freemartins)

1. A female calf, born as twin with a bull calf, but sexually imperfect (often infertile).
2. Any female animal born sterile or otherwise infertile.

   "Has your cat been spayed?" "I didn't need to: she's a freemartin."

• “freemartin” in Webster’s Seventh New Collegiate Dictionary: Based on Webster’s Third New International Dictionary, 7th edition, Springfield, Mass.: G[eorge] & C[harles] Merriam, 1963 (1967 printing), →OCLC.

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