a small ball made of wool, used for decoration, especially on a hat 小绒球（尤用以装饰帽子） 
(especially in the US) a large round bunch of thin pieces of plastic, tied to a handle, used by cheerleaders （美国啦啦队常用的）绒球，丝球
Word Originmid 18th cent. (originally denoting a bunch of ribbons, feathers, etc. worn by women in the hair or on a dress): French pompon, of unknown origin.