noun Myr·i·o·phyl·lum \ˌmirēōˈfiləm\

Definition of Myriophyllum

  1. :  a widely distributed genus of submerged aquatic plants (family Haloragaceae) having much-divided whorled or alternate leaves and emersed wind-pollinated flowers — see water milfoil

Love words? You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Join MWU now and get access to America’s largest dictionary, with:

  • 300,000 words that aren't in our free dictionary
  • Expanded definitions, etymologies, and usage notes
  • Advanced search features
  • Ad free!

Origin and Etymology of myriophyllum

New Latin, from Latin myriophyllon water milfoil, from Greek, from myrio- myri- + phyllon leaf — more at blade

Seen and Heard

What made you want to look up Myriophyllum? Please tell us where you read or heard it (including the quote, if possible).


feeling or affected by lethargy

Get Word of the Day daily email!