Source : Webster's Revised Unabridged Dictionary (1913)

Panspermy \Pan"sper`my\, n. [Pan- + Gr. ? a seed.] (Biol.)
   (a) The doctrine of the widespread distribution of germs,
       from which under favorable circumstances bacteria,
       vibrios, etc., may develop.
   (b) The doctrine that all organisms must come from living
       parents; biogenesis; -- the opposite of {spontaneous
       generation}.