tennis vs ace

tennis and ace both are nouns.

Word	Noun	Adjective	Verb	Adverb
tennis	Yes	No	No	No
ace	Yes	Yes	Yes	No

tennis (noun)	ace (noun)
a game played with rackets by two or four players who hit a ball back and forth over a net that divides the court	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

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