What does "setter" mean?

Setter: (Zoöl.) A hunting dog of a special breed originally derived from a cross between the spaniel and the pointer. Modern setters are usually trained to indicate the position of game birds by standing in a fixed position, but originally they indicated it by sitting or crouching. Note: There are several distinct varieties of setters; as, the Irish, or red, setter; the Gordon setter, which is usually red or tan varied with black; and the English setter, which is variously colored, but usually white and tawny red, with or without black.