comptroller vs controller

comptroller and controller both are nouns.

Word	Noun	Adjective	Verb	Adverb
comptroller	Yes	No	No	No
controller	Yes	No	No	No

As nouns, comptroller and controller are synonyms defined as:

comptroller and controller: someone who maintains and audits business accounts

Other synonyms of comptroller include accountant.

comptroller (noun)	controller (noun)
someone who maintains and audits business accounts	a mechanism that controls the operation of a machine
	someone who maintains and audits business accounts
	a person who directs and restrains