"What is a core subject in college?
Core academic subjects in college are the general education/core course requirements for each major, and they must be taken before starting major-specific studies. They can include basic classes in the humanities, mathematics, natural sciences, and social sciences, and they may not all be directly related to your actual major."
https://bigfuture.collegeboard.org/help-center/what-core-subject-college
"What’s the difference between elective and core subjects?
Core classes are mandatory classes you must take to meet graduation requirements in the subject areas of English, math, science, and social studies. World languages might also be considered a core class in some schools.
Electives fall outside the scope of core classes. Schools may require electives to graduate, but you may be allowed to choose the electives that you want to take, depending on your school’s offerings.
Core classes are mandatory classes you must take to meet graduation requirements in the subject areas of English, math, science, and social studies. World languages might also be considered a core class in some schools.
Electives fall outside the scope of core classes. Schools may require electives to graduate, but you may be allowed to choose the electives that you want to take, depending on your school’s offerings."
https://bigfuture.collegeboard.org/help-center/whats-difference-between-elective-and-core-subjects
https://undergrad.admissions.columbia.edu/academics/college/core