actinian

[ ak-tin-ee-uhn ]

adjective

1. belonging or pertaining to the order or suborder Actiniaria, comprising the sea anemones.

noun

1. any sea anemone.

Word History and Origins

Origin of actinian¹

1885–90; < New Latin Actini ( a ) actinia + -an

Example Sentences

Alcyonaria.—In this sub-class the zooid has very constant anatomical characters, differing in some important respects from the Actinian zooid, which has been taken as a type.

From Project Gutenberg

Diagram showing the sequence of mesenterial development in an Actinian.

From Project Gutenberg

A pause in the development follows, during which no new mesenteries are formed, and then the six-rayed symmetry characteristic of a normal Actinian zooid is completed by the formation of the mesenteries V, V in the lateral chambers, and VI, VI in the sulco-lateral chambers, their muscle-banners being so disposed that they form couples respectively with II, II and I, I. In Actinia equina the Edwardsia stage is arrived at somewhat differently.

From Project Gutenberg

Moreover, there are some modern corals in which the secondary cycle of mesenteries departs from the Actinian plan.

From Project Gutenberg

Duerden has shown that in Porites the ordinary zooids possess only six couples of mesenteries arranged on the Actinian plan.

From Project Gutenberg