Calling Card Meaning

(euphemistic) Excrement, especially of a domestic animal.

Example: 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.
1905, Alice Hegan Rice, Sandy, ch. 7:
  If Mrs. Nelson does come here, you be sure to put on your white apron before you open the door; and for pity sake don't forget the card-tray! You ought to know better than to stick out your hand for a lady's calling-card.
2006 May 14, Anne Midgette, "Summer Stages: Mozart, Yes, But Also Much More," New York Times (retrieved 26 Sep 2008):
  Free and slightly funky chamber music is the calling card of this festival.
2005 Jan. 21, Dwight Perry, "Sideline Chatter: Just doo it," Seattle Times (retrieved 26 Sep 2008):
  A guide dog left his calling card on the court at Tuesday night's Magic-Pistons game in Orlando.
A phonecard.
2003 Nov. 22, Michelle Singletary, "Traveler beware: Free things may cost you money" (retrieved 26 Sep 2008):
  Many experts now advise consumers to use a prepaid calling card to save money on long distance calls while staying in a hotel.