KNOTGRASS

knotgrass, Paspalum distichum

(noun) low-growing weedy grass with spikelets along the leaf stems

Source: WordNet® 3.1

Etymology

Noun

knotgrass (countable and uncountable, plural knotgrasses)

An annual plant, Polygonum aviculare, found in fields and wasteland.

Paspalum distichum, a weedy perennial grass of wet areas.

Synonym: water couch

Source: Wiktionary

Knot"grass`, n. (Bot.) (a) a common weed with jointed stems (Polygonum aviculare); knotweed. (b) The dog grass. See under Dog.

Note: An infusion of Polygonum aviculare was once supposed to have the effect of stopping the growth of an animal, and hence it was called, as by Shakespeare, "hindering knotgrass." We want a boy extremely for this function, Kept under for a year with milk and knotgrass. Beau. & Fl.

Source: Webster’s Unabridged Dictionary 1913 Edition