Keep one's temper under control or hold a horse in check (8)

I believe the answer is:

restrain

(Other definitions for restrain that I've seen before include "In arrest (anagram)" , "Stop" , "bottle up" , "Hold back, tether" , "stay" .)

I've seen this clue in The Irish 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.