| sciurus | (n) type genus of the Sciuridae; typical moderate-sized arboreal squirrels, Syn. genus Sciurus |
| tamiasciurus | (n) American red squirrels, Syn. genus Tamiasciurus |
| american red squirrel | (n) of northern United States and Canada, Syn. Sciurus hudsonicus, spruce squirrel, Tamiasciurus hudsonicus, red squirrel |
| chickeree | (n) far western United States counterpart of the red squirrel, Syn. Douglas squirrel, Tamiasciurus douglasi |
| eastern grey squirrel | (n) common medium-large squirrel of eastern North America; now introduced into England, Syn. cat squirrel, eastern gray squirrel, Sciurus carolinensis |
| fox squirrel | (n) exceptionally large arboreal squirrel of eastern United States, Syn. eastern fox squirrel, Sciurus niger |
| red squirrel | (n) common reddish-brown squirrel of Europe and parts of Asia, Syn. cat squirrel, Sciurus vulgaris |
| western grey squirrel | (n) large grey squirrel of far western areas of United States, Syn. western gray squirrel, Sciurus griseus |