icon

n.
  1. An image or representation; a portrait or pretended portrait.
  2. (Gr. Ch.) A sacred picture representing the Virgin Mary, Christ, a saint, or a martyr, and having the same function as an image of such a person in the Latin Church. The term is used especially for a highly stylized and conventionalized representation of a holy person, rich in symbolism and used in devotional services in many of the eastern Orthodox churches, especially the Greek and Russian Orthodox Churches.
  3. a symbol, especially a symbol whose form suggests its meaning or the object it represents.
  4. (Computers) a graphical symbol for a data object whose form suggests the nature or function of the object; especially, such a symbol as viewed on the computer screen.
  5. any object of uncritical devotion.
  6. an outstanding example of something which has come to represent the class of things to which it belongs; a paragon; used of persons as well as objects.

In a graphical user interface, pointing to and clicking on an icon may cause any of several types of actions, such as opening a file or executing a program, depending on how the icon properties are defined.