A blade with a parallel spine and edge terminating with the edge sweeping up almost to the spine and having a short, clipped-off end. Used in cattle castration applications as well as plant budding and as an ink eraser, but the same term is used for each. (“Spey” = to remove the ovaries of a female animal, but the blade is more intended for castrating males.) “Spay” is common mis-spelling.

In a cattle or stock knife, a spey blade serves the purpose for which it was named. Occasionalyl (e.g. Cattaraugus) one will find a spey blade stamped “For Flesh Only”, hinting at its use and encouraging the user to keep that blade sharp.

Obviously not for speying in the veterinary sense, this spay blade was intended as an ink eraser.

Used in a budding and grafting knife, a spey blade serves botanical purposes.