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knotgrass

British  
/ ˈnɒtˌɡrɑːs /

noun

  1. Also called: allseed.  a polygonaceous weedy plant, Polygonum aviculare, whose small green flowers produce numerous seeds

  2. any of several related plants

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

When the Prince’s Foundation took over the walled garden, it was a sea of knotgrass.

From Washington Post

“Lacewing flies, leeches, fluxweed, and knotgrass,” she murmured, running her finger down the list of ingredients.

From Literature

What, again, of weed seeds in general, and knotgrass in particular?

From Project Gutenberg

I will not say but that he may pass for an historian in Garbier's academy; he is much of the size of those knotgrass professors.

From Project Gutenberg

“There’s something else,” said Harry, watching Hermione tearing bundles of knotgrass and throwing them into the potion.

From Literature