Sex position in which the female is sprawled on the bed, face up. The man stands up on the bed and proceeds to wrestling jump on her, aiming for the vagina.

When your left testicle is stuck to the inside of your left inner thigh and your right testicle is stuck to the inside of your right inner thigh. As a result your testicles resembles the image of a flying squirrel's arms spread far apart with your scrotum and its skin being the skin on the flying squirrel's arms that droops down.
This happens often when you have been sitting down for a long time (like on an airplane or cramped bus/car) and your thighs, testicles, and scrotum start sweating and since you're so cramped and your legs aren't spread far apart, they adhesively stick to both thighs.

The species threshold above which a veterinarian will likely interrupt imminent sex to answer an emergency call. The first known example was documented in 1977 at Cold Spring Harbor Laboratory when the attending veterinarian answered a call about a flying squirrel just as things were "getting going."

Species above the flying squirrel line could include macaques, bald eagles, canines, ducks, voles, baby robins, and, of course, flying squirrels. Species likely below the flying squirrel line include danio rerio, xenopus laevis, and drosophila melanogaster.

When a person who has lost a lot of weight resulting in large skin flaps nibbles your nuts while spreading their arms wide, as if in flight.

A person who thinks they can do something, but they can't and shouldn't

A nickname I gave my dumbass friend because she like trying to fly onto her bed