visiting card vs greeting

visiting card and greeting both are nouns.

Word	Noun	Adjective	Verb	Adverb
visiting card	Yes	No	No	No
greeting	Yes	No	No	No

As nouns, greeting is a hypernym of visiting card; that is, greeting is a word with a broader meaning than visiting card:

visiting card: a printed or written greeting that is left to indicate that you have visited
greeting: (usually plural) an acknowledgment or expression of good will (especially on meeting)

Other hypernyms of visiting card include salutation.

visiting card (noun)	greeting (noun)
a printed or written greeting that is left to indicate that you have visited	(usually plural) an acknowledgment or expression of good will (especially on meeting)