disk controller vs controller

disk controller and controller both are nouns.

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

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

disk controller: (computer science) a circuit or chip that translates commands into a form that can control a hard disk drive
controller: a mechanism that controls the operation of a machine

Other hypernyms of disk controller include control.

disk controller (noun)	controller (noun)
(computer science) a circuit or chip that translates commands into a form that can control a hard disk drive	a mechanism that controls the operation of a machine
	someone who maintains and audits business accounts
	a person who directs and restrains