A hothead has a short one (4)

I believe the answer is:

fuse

'a hothead has a short one' is the definition.
(I've seen this in another clue)

This is all the clue.

(Other definitions for fuse that I've seen before include "Weld together through heat" , "Coalesce, melt together" , "Common electrical safety device in homes etc" , "Integrate" , "Join, coalesce" .)

I've seen this clue in the Universal, the L.A. Times Daily and 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.