The Collaborative International Dictionary
Panspermatist
Panspermatist \Pan*sper"ma*tist\, Panspermist \Pan"sper`mist\, n. (Biol.) A believer in panspermy; one who rejects the theory of spontaneous generation; a biogenist.
Wiktionary
panspermatist
n. (alternative form of panspermist English)