calling cardnoun [ C ]
calling card noun [ C ] (PHONE)
US also phone card a card that allows the user to make calls from anywhere and charge it to his or her home phone account
calling card noun [ C ] (VISIT)
(in the past) a card with their name on it that a person left after they had made a formal visit to someone else's house, etc.
calling card noun [ C ] (OF PERSON)
something that describes or shows a person's typical qualities:
Slow romantic songs are his calling card.