- (idiomatic) Required to.
I am supposed to report to the police every week.
Paul is supposed to call his mother every day.
- (idiomatic, with not) Permitted to.
I am not supposed to smoke there.
- (idiomatic) Intended to; expected to; believed to.
It's supposed to rain.
The thief is supposed to be hiding in the forest.
- Followed by an obligatory bare infinitive.
- (required): meant to (UK)