Keep the engine running when stationary (4)

I believe the answer is:

idle

(Other definitions for idle that I've seen before include "Futile" , "Reluctant to work - Pythonesque Eric" , "Avoiding work, lazy" , "lndolent" , "Tick over like engine" .)

I've seen this clue in The Guardian.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.