disciplinarian
🇺🇸
/ˌdɪsəplɪˈneriən/
🇬🇧
/ˌdɪsəplɪˈneəriən/
A person who is strict about rules and expects others to follow them.
The teacher is a disciplinarian, so everyone in the class behaves well.
선생님은 규율을 중시하는 사람이기 때문에 학급의 모든 학생들이 잘 행동합니다.