solitaire vs cards

solitaire and cards both are nouns.

Word	Noun	Adjective	Verb	Adverb
solitaire	Yes	No	No	No
cards	Yes	No	No	No

As nouns, cards is a hypernym of solitaire; that is, cards is a word with a broader meaning than solitaire:

Other hypernyms of solitaire include card game.

solitaire (noun)	cards (noun)
a card game played by one person	a game played with playing cards
a dull grey North American thrush noted for its beautiful song
extinct flightless bird related to the dodo
a gem (usually a diamond) in a setting by itself