Webster's Revised Unabridged Dictionary · 1913

Medusoid

Medusoid , adjective

[Medusa + -oid.]

(Zoology) Like a medusa; having the fundamental structure of a medusa, but without a locomotive disk; -- said of the sessile gonophores of hydroids.
(Zoology) A sessile gonophore. See Illust. under Gonosome.