clock-watcher noun

1. a worker who is always checking the time to make sure that they do not work longer than they need to

[TahlilGaran] English Dictionary ▲

clock watcher
n. phr., informal A worker who always quits at once when it is time; a man who is in a hurry to leave his job.
When Ted got his first job, his father told him to work hard and not be a clock watcher.

[TahlilGaran] English Idioms Dictionary ▲