- calling card, phone card - a card that is used instead of cash to make telephone calls
--1 is a kind of credit card, charge card, charge plate
- calling card, visiting card, card - a printed or written greeting that is left to indicate that you have visited
--2 is a kind of greeting, salutation
- calling card - a distinguishing characteristic or behavior; "bombs are a terrorist's calling cards"
--3 is a kind of peculiarity, distinctive feature, distinguishing characteristic