cost accountant vs controller

cost accountant and controller both are nouns.

Word	Noun	Adjective	Verb	Adverb
cost accountant	Yes	No	No	No
controller	Yes	No	No	No

As nouns, controller is a hypernym of cost accountant; that is, controller is a word with a broader meaning than cost accountant:

cost accountant: a specialist in the systematic recording and analysis of the costs incident to production
controller: someone who maintains and audits business accounts

Other hypernyms of cost accountant include accountant, comptroller.

cost accountant (noun)	controller (noun)
a specialist in the systematic recording and analysis of the costs incident to production	a mechanism that controls the operation of a machine
	someone who maintains and audits business accounts
	a person who directs and restrains