| any of various nocturnal tree squirrels, as Glaucomys volans, of the eastern U.S., having folds of skin connecting the fore and hind legs, permitting long, gliding leaps. |
| flying squirrel n. Any of various nocturnal squirrels of the genera Pteromys, Petaurista, Glaucomys, and related genera, having membranes along each side of the body between the forelegs and hind legs that enable it to glide between trees. |