Involucrum

·noun ·see Involucre.

II. Involucrum ·noun A sheath which surrounds the base of the lasso cells in the Siphonophora.

involucrum
invŏlūcrum, i, n. [involvo], that in which something is wrapped, a wrapper, covering, case, envelope...

A New Latin Dictionary by Charlton T. Lewis Ph.D. and Charles Short, LL. D.
involucrum
involūcrum ī, n 3 VOL-, a wrapper, covering, case, envelope : candelabri.—Fig., a cover, mask : s...

An Elementary Latin Dictionary