Definition of knotgrass
1 : a cosmopolitan prostrate weed (Polygonum aviculare) of the buckwheat family with jointed stems, prominent sheathing stipules, and minute flowers; broadly : any of several congeneric plants
2 : any of several grasses (such as Paspalum distichum) with markedly jointed stems
Recent Examples of knotgrass from the Web
This Series should play on a field of gout-wort, grommel and knotgrass.
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