Source : Webster's Revised Unabridged Dictionary (1913)

Spermatogonium \Sper`ma*to*go"ni*um\, n. [NL., fr. Gr. ????,
   ???, sperm + ??? offspring.] (Physiol.)
   A primitive seminal cell, occuring in masses in the seminal
   tubules. It divides into a mass (spermosphere) of small cells
   (spermoblast), which in turn give rise to spermatozoids.