rhizostome
/ˈrʌɪzəstəʊm/Zoology
noun
Any jellyfish of the scyphozoan order Rhizostomeae (or Rhizostomae), characterized by having eight highly branched oral arms containing numerous tiny suctorial mouths, and by a lack of tentacles.
Origin
Early 19th century; earliest use found in Belfast Monthly Magazine. From rhizo- + -stome, after either scientific Latin Rhizostoma, genus name or French rhizostome. In later use perhaps also partly after scientific Latin Rhizostomeae (or Rhizostomae), order name.