sign on
US /saɪn ɑːn/
UK /saɪn ɑːn/

1.
2.
to begin a period of work
:
•
The night shift workers will sign on at 10 PM.
•
The crew will sign on early tomorrow morning.
3.
to register as unemployed to receive benefits
:
•
After losing his job, he had to sign on at the unemployment office.
•
She's been signing on for benefits for six months now.