A review of a situation or system is its formal examination by people in authority. This is usually done in order to see whether it can be improved or corrected.

If you review a situation or system, you consider it carefully to see what is wrong with it or how it could be improved.

A review is a report in the media in which someone gives their opinion of something such as a new book or film.

If someone reviews something such as a new book or film, they write a report or give a talk on television or radio in which they express their opinion of it.

When a military or political leader reviews troops, they examine them, or watch them marching.

When you review for an examination, you read things again and make notes in order to be prepared for the examination.