A noun "discipline" represents a controlled behavior or self-control, enforced compliance or control, a systematic method of obtaining obedience, a state of order based on submission to authority, a set of rules regulating behavior, and a punishment or method used to train or maintain control.

A specific branch of knowledge, learning, or practice, and also a category in which a certain art, sport, or other activity belongs.

(transitive) To train someone by instruction and practice.

(transitive) To teach someone to obey authority.

(transitive) To punish someone in order to (re)gain control.

(transitive) To impose order on someone.