IDIOMS

button nose

(idiomatic) A person having such a nose.

Example: 1909, H. G. Wells, Tono Bungay, ch. 2:
  She had little features, a button nose, a pretty chin and a long graceful neck.
1993 June 6, Edmund White, "Sapristi! Is This Our Tintin?" (review of Tintin in the New World: A Romance by Frederic Tuten), New York Times (retrieved 17 May 2014):
  Tintin, the comic strip hero with the button nose, poppy-seed eyes and blond flip hairdo, is now an institution.
2001 July 30, Josh Tyrangiel, "People: With these rings, we thee sue," Time (retrieved 17 May 2014):
  You can't buy BRAD PITT's icy blue eyes or JENNIFER ANISTON's adorable button nose.
1961 July 7, "Cinema: Adults Are Boobs," Time (retrieved 17 May 2014):
  Surprisingly, the film is delightful—mostly because of 15-year-old Hayley Mills, the blonde button nose who played the endearing delinquent in Tiger Bay.