Definition of "balloon" []

• A flexible bag designed to be inflated with hot air or with a gas, such as helium, that is lighter than the surrounding air, causing it to rise and float in the atmosphere. (noun)
• Such a bag with sufficient capacity to lift and transport a suspended gondola or other load. (noun)
• Such a bag shaped like a figure or object when inflated; an inflatable. (noun)
• A usually round or oblong inflatable rubber bag used as a toy. (noun)
• Medicine A sac that is inserted into a body cavity or tube and distended with air or gas for therapeutic purposes, such as angioplasty. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• ""I shall," says he, "make a balloon -- the _last balloon_ -- in proportions extraordinarily gigantic, twenty times larger than the largest, which shall realise that which has never been but a dream in the American journals, which shall attract, in France, England, and America, the crowd always ready to run to witness the most insignificant ascent."
• "Her word balloon is split in half by Joker firing the gun."
• "To open up the narrow valve, the balloon is briefly inflated, deflated and withdrawn."