1. aquatic or marsh-growing fern allies; known to have existed since the Cenozoic; sometimes included in Lycopodiales; [syn: Isoetales, order Isoetales]
WordNet (r) 3.0 (2006):
order Isoetales
n 1: aquatic or marsh-growing fern allies; known to have existed
since the Cenozoic; sometimes included in Lycopodiales
[syn: Isoetales, order Isoetales]