Definify.com
Webster 1913 Edition
Polygonum
‖
Po-lyg′o-num
,Noun.
[NL., fr. Gr. [GREEK] a kind of plant;
πολύσ
many + γόνυ
the knee, a joint of a plant. So called in allusion to the numerous joints.] (Bot.)
A genus of plants embracing a large number of species, including bistort, knotweed, smartweed, etc.