catch on
phrasal verb with catch verb [ T ] uk/kætʃ/ uscaught | caught
to become popular:
He invented a type of virtual reality helmet, but it never caught on.
Online trading has been slow to catch on in this part of the country.
to understand something:
Younger people catch on right away. It is older people that need to be convinced.
catch on to sth They are slowly catching on to the fact that this decision has made them very unpopular.