Accurate clock (11)
I believe the answer is:
chronometer
(Other definitions for chronometer that I've seen before include "Accurate timepiece" , "Instrument measuring time" .)
I've seen this clue in The Guardian.
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.