alcyonarian

noun

al·​cy·​o·​nar·​ian ˌal-sē-ə-ˈner-ē-ən 

: any of a subclass (Alcyonaria) of colonial anthozoans (such as the sea pens) having polyps with eight branched tentacles and eight septa

Word History

Etymology

ultimately from Greek alkyoneion, a zoophyte, from neuter of alkyoneios of a kingfisher, from alkyon kingfisher; from its resemblance to a kingfisher's nest

First Known Use

1861, in the meaning defined above