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polygonaceous

[pol-ee-guh-ney-shuh s, puh-lig-uh-ney-]
adjective
  1. belonging to the Polygonaceae, the buckwheat family of plants.
Compare buckwheat family.

Origin of polygonaceous

1870–75; < New Latin Polygonace(ae) (Polygon(um) the type genus (< Greek polýgonon knotgrass, literally, something with many joints; see poly-, knee, -gon) + -aceae -aceae) + -ous
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for polygonaceous

polygonaceous

adjective
  1. of, relating to, or belonging to the Polygonaceae, a chiefly N temperate family of plants having a sheathing stipule (ocrea) clasping the stem and small inconspicuous flowers: includes dock, sorrel, buckwheat, knotgrass, and rhubarb
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