Slotted piece that fits behind a padlock (4)

I believe the answer is:

hasp

(Other definitions for hasp that I've seen before include "Fastening plate, clasp" , "Hinged fastening" , "Door latch" , "This part of fastening device" , "catch" .)

I've seen this clue in The New York Times.

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.