calling card vs peculiarity

calling card and peculiarity both are nouns.

Word	Noun	Adjective	Verb	Adverb
calling card	Yes	No	No	No
peculiarity	Yes	No	No	No

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

Other hypernyms of calling card include distinctive feature, distinguishing characteristic.

calling card (noun)	peculiarity (noun)
a distinguishing characteristic or behavior	something unusual -- perhaps worthy of collecting
a printed or written greeting that is left to indicate that you have visited	a distinguishing trait
a card that is used instead of cash to make telephone calls	an odd or unusual characteristic