watch the clock
To continually check the time because one desires something to end, typically because one is bored or is anxiously waiting to start a different activity. I was supposed to work on that spreadsheet, but I just watched the clock for the last two hours. Quit watching the clock and pay attention, Janine. We still have a lot of material to cover before class ends.
watch the clock
wait eagerly for the end of working hours. It is from this expression that the word clock-watcher has developed, referring to someone who is determined not to work more than their allotted hours.
watch the ˈclock
(disapproving) often check what time it is, because you are impatient for something to finish or to happen: Someone who spends all their time watching the clock is usually not a good worker. ▶ ˈclock-watching noun: Don’t spend the afternoon clock-watching. ˈclock-watcher noun