1.nounSomething that must be gained in order to gain something else
"A degree is a prerequisite for entry into this profession."
2.nounIn education, a course or topic that must be completed before another course or topic can be started. May be colloquially referred to as a prereq.
"Algebra is typically a prerequisite for physics."
3.adjectiveRequired as a prior condition of something else; necessary or indispensable.
"The prerequisite warm-up to the match was ignored."