Polygon :: Polygon (n.) A plane figure having many angles, and consequently many sides; esp., one whose perimeter consists of more than four sides; any figure having many angles..
Polygonaceous :: Polygonaceous (a.) Of or pertaining to a natural order of apetalous plants (Polygonaceae), of which the knotweeds (species of Polygonum) are the type, and which includes also the docks (Rumex), the buckwheat, rhubarb, sea grape (Coccoloba), and several other genera..