flying opossum vs flying squirrel

flying opossum and flying squirrel both are nouns.

Word	Noun	Adjective	Verb	Adverb
flying opossum	Yes	No	No	No
flying squirrel	Yes	No	No	No

As nouns, flying opossum and flying squirrel are synonyms defined as:

flying opossum and flying squirrel: nocturnal phalangers that move with gliding leaps using parachute-like folds of skin along the sides of the body

Other synonyms of flying opossum include flying phalanger.

flying opossum (noun)	flying squirrel (noun)
nocturnal phalangers that move with gliding leaps using parachute-like folds of skin along the sides of the body	nocturnal phalangers that move with gliding leaps using parachute-like folds of skin along the sides of the body