ATM aperture (4)

I believe the answer is:

slot

(Other definitions for slot that I've seen before include "Opening for coin or TV programme" , "Scheduled time -- aperture for coins" , "Narrow opening as in gaming machine" , "Opening (for coins)" , "Hole for e.g. coin" .)

I've seen this clue in The Washington Post.

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.