ˌspīrəˈdēlə noun
Usage: capitalized
Etymology: New Latin, from spir- + -dela (from Greek dēlos visible, evident); from the fact that the spiral vessels are visible through the transparent tissues — more at adel-
: a genus of aquatic plants (family Lemnaceae) having a membranous spathe and a thallus with a cluster of several rootlets — see great duckweed