from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Any of certain grasses of the genus Digitaria, especially D. sanguinalis or D. ischaemum, widely naturalized in North America.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A member of the genus Digitaria, a grass of tropical to temperate climates, and a major pest of lawns in such climates, mainly from their invasive habits and the fact they die off in the fall and winter, leaving ugly bare patches.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. grasses with creeping stems that root freely; a pest in lawns
crab + grass (Wiktionary)