Wiktionary
n. (context cycling English) A trick in which the body of the bike is rotated around the handlebar.
Wikipedia
The tailwhip is a bike trick typically performed on a BMX, in which the frame of the bike performs a complete rotation around the front end (bars and forks), which remains stationary throughout the move. The same trick may also be performed on a kick scooter.
To do the trick there are a few main methods: these both include whipping the bike around using your arms in a gyrating motion whilst holding the bars, but some riders also kick the bike with their back foot to give it extra momentum. It also helps if you approach a jump crooked, which will throw the bike from under, allowing you to start a tailwhip.
Usage examples of "tailwhip".
It lay in a tangle of claw-tipped limbs, the acid from its tailwhip slowly eating its way through the floor covering.
Sun-hes said, clicking his mandibles and snapping his tailwhip in amusement, "we have sayings like that ourselves.
She put her pedipalps up to hold them still and her tailwhip began to vibrate.