Cause of a grimace (4)

I believe the answer is:

pain

(Other definitions for pain that I've seen before include "Symptom of hurt or disorder" , "Bodily suffering or mental anguish" , "Tiresome figure" , "Physical hurt" , "can cause discomfort" .)

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.