The Collaborative International Dictionary of English v.0.48:

Spermatozoon \Sper`ma*to*zo"on\, n.; pl. Spermatozoa. [NL.,
   fr. Gr. ???, sperm + zo^,on an animal.] (Biol.)
   Same as Spermatozoid.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

23 Moby Thesaurus words for "spermatozoa":
   androcyte, antheridium, antherozoid, male gamete, milt, pollen,
   protein, scum, seed, semen, seminal fluid, sperm, sperm cell,
   spermagonium, spermatic fluid, spermatid, spermatiophore,
   spermatium, spermatocyte, spermatogonium, spermatophore,
   spermatozoid, spermatozoon