mean business

To be very serious about completing a task or doing something, ardent; serious, not jokingly

I see you mean business.

I could tell my teacher meant business when she said that she would fail me unless I completed my homework.

by L0NdA August 15, 2008

Mean business

To be completely serious about something.

Alice: Here comes Charlie. Wait, what is he doing with that chainsaw?
Bob: Uh oh. I hope he doesn't mean business.

by MalumLibrum958 September 20, 2023