pompom

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A fluffy ball of wool or other material used as a decoration, as on a cap.
• noun A ball of fluffy material, such as feathers or strips of colored paper, that is waved by cheerleaders and sports fans.
• noun A small buttonlike flower of some chrysanthemums and dahlias.

from The Century Dictionary.

• noun A one-pounder automatic Maxim gun.
• noun A religious dance observed by the Yakima Indians of Washington, similar in character to the religious dances held by other tribes of the plateaus of Washington, Idaho, Montana, and British Columbia. It seems that the pompom relates to the belief of the return of the dead. Young people have the right to contract marriages during these dances.

from the GNU version of the Collaborative International Dictionary of English.

• noun an ornamental ball or tuft of wool, feathers, or other fluffy material used as a decoration on clothing such as hats and slippers.
• noun a pompon.
• noun (Mil.) 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.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun onomatopoeia A decorative ball made of pieces of soft fabric bound at the centre, most notably used in cheerleading

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun decoration consisting of a ball of tufted wool or silk; usually worn on a hat
• noun artillery designed to shoot upward at airplanes