Green’s Dictionary of Slang

(US/W.I.) the testicles.

1988		J.D. Vigil in Ethos 432: It is doing these ‘gang’ things that earnis you the respect [...] as a dependanble gang member with ‘huevos’ (balls).
2000		R. Antoni Grandmother’s Erotic Folktales 42: Two hairy huevos, and a cornstarch-plaster stuck up between his legs.