To save this word, you'll need to log in.
Definition of water fern
1 : a fern ally of the families Salviniaceae or Marsileaceae
2 : a fern of the genus Osmunda (especially O. regalis)
Comments on water fern
What made you want to look up water fern? Please tell us where you read or heard it (including the quote, if possible).
Test Your Vocabulary
Obscure Shapes
- Something that is ooid is shaped like:
Can you spell these 10 commonly misspelled words?
TAKE THE QUIZ
Test Your Knowledge - and learn some interesting things along the way.
TAKE THE QUIZLove words? Need even more definitions?
Merriam-Webster unabridgedWords at Play
Ask the Editors
Word Games
Share water fern