memory apparatus vs apparatus

memory apparatus and apparatus both are nouns.

Word	Noun	Adjective	Verb	Adverb
memory apparatus	Yes	No	No	No
apparatus	Yes	No	No	No

As nouns, apparatus is a hypernym of memory apparatus; that is, apparatus is a word with a broader meaning than memory apparatus:

memory apparatus: An outdated mechanical device used for presenting a series of stimuli to be memorized.
apparatus: equipment designed to serve a specific function

Other hypernyms of memory apparatus include setup.

memory apparatus (noun)	apparatus (noun)
An outdated mechanical device used for presenting a series of stimuli to be memorized.	equipment designed to serve a specific function
	(anatomy) a group of body parts that work together to perform a given function