intransitive verb
1. : to seize hold : attach oneself
the swimmer caught on to the back of the boat
2. : understand , learn , tumble
the police caught on to what he was doing
you can catch on to the job in two or three days
3. : to become popular
this movement has already caught on in other states — Bernard Smith
4. : to get a job
he finally caught on as a chore boy with an outfit in New Mexico — Ross Santee