a combining form meaning "seed"; used with this meaning and as a combining form of sperm 1 in the formation of compound words: spermatogonium. Also, esp. before a vowel, spermat- . Cf. sperm-, -sperm, -spermal, -spermic, spermo-, -spermous .
[ spermat- (s. of spérma; see SPERM 1 ) + -O- ]