Meaning of STRICTLY in English

strict ‧ ly /ˈstrɪktli/ BrE AmE adverb

1 . in a way that must be obeyed:

Alcohol is strictly forbidden on school premises.

The ban on hunting is not strictly enforced.

2 . exactly and completely:

That isn’t strictly true.

3 . strictly speaking used to say that something is true if you are going to be very exact and correct about it:

Strictly speaking, spiders are not insects.

4 . only for a particular person, thing, or purpose and no one else:

This is strictly between us. Nobody else must know.

Longman Dictionary of Contemporary English.      Longman - Словарь современного английского языка.