auditor vs pupil

auditor and pupil both are nouns.

Word	Noun	Adjective	Verb	Adverb
auditor	Yes	No	No	No
pupil	Yes	No	No	No

As nouns, pupil is a hypernym of auditor; that is, pupil is a word with a broader meaning than auditor:

Other hypernyms of auditor include educatee, student.

auditor (noun)	pupil (noun)
a qualified accountant who inspects the accounting records and practices of a business or other organization	the contractile aperture in the center of the iris of the eye; resembles a large black dot
someone who listens attentively	a learner who is enrolled in an educational institution
a student who attends a course but does not take it for credit	a young person attending school (up through senior high school)