It goes beep (4)

I believe the answer is:

horn

(Other definitions for horn that I've seen before include "Wind instrument - cape" , "Musical instrument; Chile Cape" , "Musical instrument - antler" , "Cusp" , "Head growth; cornucopia" .)

I've seen this clue in the Universal.

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.