1. Of a timer or something similar, to show the time decreasing to some amount or the point at which something ends. I had to sit in detention after class each week, watching the clock tick down to 5 PM. We set up a timer beside our chess board and tried to finish each game before it ticked down all the way.
2. Of some amount or period of time, to decrease or draw to an end. We only had five more weeks until the deadline, and it felt like time kept ticking down faster each day. I always hated the feeling of the summer ticking down when I was a kid.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.