‖n. [ NL., fr. Gr. "y`alos glass + &unr_; a thread.] (Zool.) A genus of hexactinelline sponges, having a long stem composed of very long, slender, transparent, siliceous fibres twisted together like the strands of a color. The stem of the Japanese species (Hyalonema Sieboldii), called glass-rope, has long been in use as an ornament. See Glass-rope. [1913 Webster]