card index vs file cabinet

card index and file cabinet both are nouns.

Word	Noun	Adjective	Verb	Adverb
card index	Yes	No	No	No
file cabinet	Yes	No	No	No

As nouns, file cabinet is a hypernym of card index; that is, file cabinet is a word with a broader meaning than card index:

card index: an alphabetical listing of items (e.g., books in a library) with a separate card for each item
file cabinet: office furniture consisting of a container for keeping papers in order

Other hypernyms of card index include file, filing cabinet.

card index (noun)	file cabinet (noun)
an alphabetical listing of items (e.g., books in a library) with a separate card for each item	office furniture consisting of a container for keeping papers in order