- a fern, Thelypteris palustris, having pinnatifid fronds and growing in wet places.
Origin of marsh fern
First recorded in 1855–60
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- a fern of marshy woodlands, Thelypteris palustris, having pale green pinnate leaves and an underground rootstock