Meaning of “concentrate” - Learner’s Dictionary

concentrate

verb us uk /ˈkɒnsəntreɪt/
Stop it! I can't concentrate if you keep making a noise.He will keep talking when I'm trying to concentrate.I find it hard to concentrate when there's music playing.It's one of those tasks that you really need to concentrate on.He frowns when he's concentrating.

B1 [ I ] to think very carefully about something you are doing and nothing else:

Be quiet - I'm trying to concentrate.
I can't concentrate on my work. It's too noisy here.
be concentrated around/in/on, etc

to be present in large numbers or amounts in a particular area:

Most of the fighting was concentrated in the mountains.

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