SPIRALOZOOID

Spi*ra`lo*zo"oid, n. Etym: [Spiral + zooid. So called because they often have a spiral form when contracted.] (Zoöl.)

Definition: One of the special defensive zooids of certain hydroids. They have the form of long, slender tentacles, and bear lasso cells.

Source: Webster’s Unabridged Dictionary 1913 Edition