From Longman Dictionary of Contemporary Englishwatch the clockwatch the clockinformalNOT DO something to keep looking at the time because you are worried or bored anxious mums watching the clock → watch
Examples from the Corpus
watch the clock• I am watching the clock, counting the minutes till the last period of the morning is over.• She watched the clock hands go round.• And watched the clock so he could call a halt to it as soon as possible.• Only then did she let herself watch the clock to the strains of Beethoven's Apassionata. 