from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Any of numerous plants of the widely distributed genus Polygonum, characterized by stems with knotlike joints and conspicuous sheathlike stipules.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Any of many plants, of the family Polygonaceae, embracing a large number of species, including bistort, knotweed, smartweed, etc.
New Latin Polygonum, genus name, from Greek polugonon, knotgrass : polu-, poly- + gonu, knee; see genu-1 in Indo-European roots.(American Heritage® Dictionary of the English Language, Fourth Edition)
New Latin, from Greek a kind of plant; many + the knee, a joint of a plant. So called in allusion to the numerous joints (Wiktionary)