Definition of: gun metal

1. A bronze alloy, composed of nine parts copper to one part tin, formerly much used for smaller cannon, and still used for other purposes.
2. Any other material used in making guns, as gun iron, steel, certain kinds of brass, etc.
3. Any of various alloys treated with sulfur or the like to imitate the color of gun metal: used for metal novelties.
4. A neutral gray color with a bluish tinge: also gun-met·al gray (gun′met′l).