Green’s Dictionary of Slang

1. (US) to toggle an airplane engine on and off.

1937

(con. WW1) E.C. Parsons Great Adventure 44: The stick in the Blériot had [...] a contact button [...] so that the motor could be blipped on and off.

2. (US) to flash one’s headlights.

2023

(con. 1962) J. Ellroy Enchanters 15: Headlight blips hit me [...] I blipped back.