Definition of polygonum
: any of a genus (Polygonum) of herbs of the buckwheat family with a prominent tubular sheath around the base of each petiole, thickened nodes, and flowers that are solitary and axillary or in spiked racemes —called also knotweed
Origin of polygonum
New Latin, from Greek polygonon knotgrass, from poly- + gony knee — more at knee
First Known Use: circa 1706
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