What is the meaning of Calling_card?

A small printed card which identifies the bearer, traditionally presented for introduction when making a social visit to a home or when attending a formal social event or business meeting.

An attribute, symptom, object, or behavior which is distinctly characteristic of someone or something.

Excrement, especially of a domestic animal.

A phonecard.

A card advertising the services of a prostitute.

An explosive dropped from a bomber aeroplane.

Source: wiktionary.org