comprehensive vs exam

comprehensive and exam both are nouns.

Word	Noun	Adjective	Verb	Adverb
comprehensive	Yes	Yes	No	No
exam	Yes	No	No	No

As nouns, exam is a hypernym of comprehensive; that is, exam is a word with a broader meaning than comprehensive:

comprehensive: an intensive examination testing a student's proficiency in some special field of knowledge
exam: a set of questions or exercises evaluating skill or knowledge

Other hypernyms of comprehensive include examination, test.

comprehensive (noun)	exam (noun)
an intensive examination testing a student's proficiency in some special field of knowledge	a set of questions or exercises evaluating skill or knowledge

comprehensive (adjective)	exam (adjective)
including all or everything
broad in scope