'Pillwort' definitions:

Definition of 'pillwort'

(from WordNet)
noun
European water fern found around margins of bodies of water or in wet acid soil having small globose sporocarps [syn: pillwort, Pilularia globulifera]

Definition of 'Pillwort'

From: GCIDE
  • Pillwort \Pill"wort`\, n. (Bot.) Any plant of the genus Pilularia; minute aquatic cryptograms, with small pill-shaped fruit; -- sometimes called peppergrass. [1913 Webster]