What is Revert ?

Revert is (verb) 1. to go back or come back to an earlier state to revert to type or form to go back to an original state We thought he was becoming a quiet intellectual, then he reverted to form and went out drinking every night. 2. to revert to a subject to start talking about the subject again (formal.) I would like to revert to the subject of overdue payments. The conversation reverted to the question of planning permission.


source: Easier English, Student Dictionary Upper Intermediate Level