What does "clock on" mean?

To record one's time of arrival at work, traditionally by inserting one's card into a timestamping machine.

What is a synonym for "clock on"?

Common synonyms include: clock in, punch in.

verb, slang

verb, slang ·Moderate ·College level

Verb

1
To record one's time of arrival at work, traditionally by inserting one's card into a timestamping machine. UK, literally
2
register one's arrival at work wordnet
3
To begin work at the start of the day or start of one's shift. UK, broadly
4
To grow older; to proceed. informal, intransitive
"His birthday was another reminder of his life clocking on."

"His birthday was another reminder of his life clocking on."