groundhog

CIDE DICTIONARY

groundhog, n. 

 A reddish brown North American burrowing marmot (Marmota monax), also called the woodchuck. It hibernates in the winter.  [WordNet 1.5]

OXFORD DICTIONARY

groundhog, n.
1 = AARDVARK.
2 US a marmot; a woodchuck.

THESAURUS

groundhog

Cape polecat, ape, bar, bear, cavy, chimp, chimpanzee, coon, digger, dredge, dredger, driller, excavator, ferret, foumart, glutton, guinea pig, hedgehog, miner, monk, monkey, mousehound, navvy, opossum, polecat, porcupine, possum, prairie dog, quill pig, raccoon, sandhog, sapper, skunk, steam shovel, tunneler, weasel, whistle-pig, wolverine, woodchuck, zoril