·add. ·noun A smokeless powder composed of nitroglycerin, guncotton, and mineral jelly, and used by the British army and in other services. In making it the ingredients are mixed into a paste with the addition of acetone and pressed out into cords (of various diameters) resembling brown twine, which are dried and cut to length. A variety containing less nitroglycerin than the original is known as cordite M. D.