a. and sb. Zool. [ad. mod.L. Tetractinellidæ (f. Gr. τετρα-, TETRA- + ἀκτίς (ἀκτῖν-) ray + L. dim. -ella): see -ID.] a. adj. Belonging to the Tetractinellidæ (also called Tetractina), a sub-order of siliceous sponges with four-rayed spicules. b. sb. A sponge of this order. So Tetractinellidan a. and sb., Tetractinelline a.
1891. Cent. Dict., Tetractinellidan, Tetractinelline.
1892. Nat. Sc., March, 20. Tetractinellid spicules … occur … in the shallower regions.
1892. Athenæum, 13 Feb., 218/2. The sponge remains … belong largely to the Monactinellidæ though tetractinellid, lithistid, and hexactinellid spicules are also present.
