Etymology From self- + mastery. Noun self-mastery (uncountable) The conscious control of one's behaviour. Synonyms: self-command, self-control, self-discipline, self-regulation Antonym: undisciplinedness Hyponym: self-restraint Coordinate terms: self-awareness, self-criticism Near-synonym: willpower Self-mastery matters for everyone. Translations conscious control of one's own behaviour — see self-control, self-discipline, self-restraint