Meaning of “about” - Learner’s Dictionary

about

adverb uk us /əˈbaʊt/
APPROXIMATELY

A1 used before a number or amount to mean approximately:

It happened about two months ago.
DIRECTION (also US around)

B2 to or in different parts of a place, often without purpose or order:

She's always leaving her clothes lying about.
NEAR informal (also US around)

If someone or something is about, they are near to the place where you are now:

Is Kate about?
be about to do sth

B2 to be going to do something very soon:

I stopped her just as she was about to leave.

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