The Collaborative International Dictionary of English v.0.48:

Gonad \Gon"ad\, n.; pl. Gonads. [Gr. ? that which generates.]
   (Anat.)
   One of the masses of generative tissue primitively alike in
   both sexes, but giving rise to either an ovary or a testis; a
   generative gland; a germ gland. --Wiedersheim.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

45 Moby Thesaurus words for "gonads":
   bag, ballocks, balls, basket, beard, breasts, cervix, clitoris,
   cod, cods, cullions, family jewels, female organs, genitalia,
   genitals, labia, labia majora, labia minora, lingam, lips,
   male organs, meat, nuts, nymphae, ovary, penis, phallus,
   private parts, privates, privy parts, pubic hair, pudenda,
   reproductive organs, rocks, scrotum, secondary sex characteristic,
   sex organs, spermary, testes, testicles, uterus, vagina, vulva,
   womb, yoni