read-only storage vs storage

read-only storage and storage both are nouns.

Word	Noun	Adjective	Verb	Adverb
read-only storage	Yes	No	No	No
storage	Yes	No	No	No

As nouns, storage is a hypernym of read-only storage; that is, storage is a word with a broader meaning than read-only storage:

read-only storage: (computer science) memory whose contents can be accessed and read but cannot be changed
storage: an electronic memory device

Other hypernyms of read-only storage include computer memory, computer storage, memory, memory board, store.

read-only storage (noun)	storage (noun)
(computer science) memory whose contents can be accessed and read but cannot be changed	the commercial enterprise of storing goods and materials
	the act of storing something
	depositing in a warehouse
	a depository for goods
	an electronic memory device
	(computer science) the process of storing information in a computer memory or on a magnetic tape or disk