ace of clubs vs ace

ace of clubs and ace both are nouns.

Word	Noun	Adjective	Verb	Adverb
ace of clubs	Yes	No	No	No
ace	Yes	Yes	Yes	No

As nouns, ace is a hypernym of ace of clubs; that is, ace is a word with a broader meaning than ace of clubs:

ace of clubs (noun)	ace (noun)
the ace in the club suit	a serve that the receiver is unable to reach
	one of four playing cards in a deck having a single pip on its face
	someone who is dazzlingly skilled in any field
	the smallest whole number or a numeral representing this number

ace of clubs (adjective)	ace (adjective)
	of the highest quality