The Collaborative International Dictionary of English v.0.48:

Testes \Tes"tes\, n.,
   pl. of Teste, or of Testis.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Testis \Tes"tis\, n.; pl. Testes. [L.] (Anat.)
   A testicle.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

45 Moby Thesaurus words for "testes":
   bag, ballocks, balls, basket, beard, breasts, cervix, clitoris,
   cod, cods, cullions, family jewels, female organs, genitalia,
   genitals, gonads, 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, testicles, uterus, vagina, vulva, womb,
   yoni



Bouvier's Law Dictionary, Revised 6th Ed (1856):

TESTES. Witnesses.