资料来源 : Webster's Revised Unabridged Dictionary (1913)

Spermatogenesis \Sper`ma*to*gen"e*sis\, n. [Spermato- +
   genesis.] (Biol.)
   The development of the spermatozoids.

资料来源 : WordNet®

spermatogenesis
     n : development of spermatozoa