'floating fern' definitions:

Pantropical aquatic fern [syn: floating fern, Ceratopteris thalictroides]

Aquatic fern of tropical America often used in aquariums [syn: floating fern, water sprite, Ceratopteris pteridioides]

Small free-floating aquatic fern from the eastern United States to tropical America; naturalized in western and southern Europe [syn: mosquito fern, floating fern, Carolina pond fern, Azolla caroliniana]