The term 'BOOK IT!' is a phrase that is used to encourage someone to take action and do something quickly. The crossword solutions for this term are READ (4 letters) and ROOM (4 letters). READ suggests that the person should take the time to READ up on the topic or task they are being asked to do, while ROOM implies that they should find a place to work on it. Both of these solutions suggest that the person should take the initiative to get started on the task at hand.