Meaning of “imagine” - Learner’s Dictionary

imagine

verb [ T ] uk us /ɪˈmædʒɪn/
CREATE

B1 to create an idea or picture of something in your mind:

[ + doing sth ] Imagine being able to travel in space.
[ + question word ] You can imagine how pleased I was when the letter arrived.
BELIEVE

B2 to believe that something is probably true:

I imagine he must be under a lot of pressure at the moment.
NOT REAL

B1 to think that you hear or see something that does not really exist:

I can't hear anything - you must be imagining it.

(Definition of “imagine” from the Cambridge Learner’s Dictionary © Cambridge University Press)