n. originally, a Vickers-Maxim one-pounder automatic machine cannon using metallic ammunition fed from a lopped belt attached to the gun; -- popularly so called from its peculiar drumming sound in action. More recently, the term is applied mostly to automatic antiaircraft cannons.n. an ornamental ball or tuft of wool, feathers, or other fluffy material used as a decoration on clothing such as hats and slippers.n. a pompon.