To sharply poke or pinch someone's buttocks. Derived from a goose's inclination to bite at a retreating intruder's hindquarters.
To stimulate, to spur.
To gently accelerate an automobile or machine, or give repeated small taps on the accelerator.
(UK slang) Of private-hire taxi drivers, to pick up a passenger who has not pre-booked a cab. This is unauthorised under UK licensing conditions.
To hiss (a performer) off the stage.