The Collaborative International Dictionary
Rhodosperm
Rhodosperm \Rho"do*sperm\, n. [Gr. "ro`don the rose + spe`rma a seed.] (Bot.) Any seaweed with red spores.
Note: As the name of a subclass, Rhodosperms, or Rhodosperme[ae], is synonymous with Floride[ae] (which see.)
Wiktionary
rhodosperm
n. Any seaweed with red spores.