The Collaborative International Dictionary
Spado \Spa"do\, n.; pl. Spadones. [L., fr. Gr. ?.]
Same as Spade,
2. (Law) An impotent person.
Douglas Harper's Etymology Dictionary
"castrated person," early 15c., from Latin spado, from Greek spadix, related to spadon "eunuch," span "to draw, tear away" (see spay).
n. (context now rare English) Someone who has been castrated; a eunuch or castrato.