The term 'tells off' can be defined as scolding, rebuking, chiding, or railing against someone. Scolding is a form of verbal reprimand that is used to express disapproval or disappointment. Rebuking is a stronger form of scolding, and involves expressing strong disapproval or criticism. Chiding is a milder form of scolding, and usually involves teasing or mocking someone. Railing is the most extreme form of scolding, and involves shouting or screaming at someone in an angry manner. All of these terms are related to the phrase 'tells off, ' and can be used to describe the same action.