noun
compulsory subject; required subject
Refers to a subject or course that students must take, as opposed to an elective.
この大学では、英語が必修科目です。
At this university, English is a compulsory subject.
選択科目 means 'elective subject', the opposite of 必修科目.
Compound of 必修 (compulsory) + 科目 (subject).