balloon

American  

[buh-loon] / bəˈlun /

noun

1. a bag made of thin rubber or other light material, usually brightly colored, inflated with air or with some lighter-than-air gas and used as a children's plaything or as a decoration.

2. a bag made of a light material, as silk or plastic, filled with heated air or a gas lighter than air, designed to rise and float in the atmosphere and often having a car or gondola attached below for carrying passengers or scientific instruments.

3. (in drawings, cartoons, etc.) a balloon-shaped outline enclosing words represented as issuing from the mouth of the speaker.

4. an ornamental ball at the top of a pillar, pier, or the like.

5. a large, globular wineglass.

6. Chemistry Now Rare. a round-bottomed flask.

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verb (used without object)

1. to go up or ride in a balloon.

2. to swell or puff out like a balloon.

3. to multiply or increase at a rapid rate.

   Membership has ballooned beyond all expectations.

verb (used with object)

1. to fill with air; inflate or distend (something) like a balloon.

adjective

1. puffed out like a balloon.

   balloon sleeves.

2. Finance. (of a loan, mortgage, or the like) having a payment at the end of the term that is much bigger than previous ones.

balloon British  

/ bəˈluːn /

noun

1. an inflatable rubber bag of various sizes, shapes, and colours: usually used as a plaything or party decoration

2. a large impermeable bag inflated with a lighter-than-air gas, designed to rise and float in the atmosphere. It may have a basket or gondola for carrying passengers, etc See also barrage balloon hot-air balloon

3. a circular or elliptical figure containing the words or thoughts of a character in a cartoon

4. 1. a kick or stroke that propels a ball high into the air

   2. ( as modifier )

      a balloon shot

5. chem a round-bottomed flask

6. a large rounded brandy glass

7. commerce

   1. a large sum paid as an irregular instalment of a loan repayment

   2. ( as modifier )

      a balloon loan

8. surgery

   1. an inflatable plastic tube used for dilating obstructed blood vessels or parts of the alimentary canal

   2. ( as modifier )

      balloon angioplasty

9. informal to be completely unsuccessful or unpopular

10. informal when the trouble or action begins

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verb

1. (intr) to go up or fly in a balloon

2. (intr) to increase or expand significantly and rapidly

   losses ballooned to £278 million

3. to inflate or be inflated; distend; swell

   the wind ballooned the sails

4. (tr) to propel (a ball) high into the air

balloon Idioms  

More idioms and phrases containing balloon

• go over (like a lead balloon)
• trial balloon

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Other Word Forms

• balloon-like adjective
• ballooning noun
• balloonist noun
• balloonlike adjective

Etymology

Origin of balloon

1570–80; < Upper Italian ballone, equivalent to ball ( a ) (< Langobardic; ball ¹ ) + -one augmentative suffix; or < Middle French ballon < Upper Italian

Explanation

A balloon is a colorful bit of rubber that can be blown up or filled with helium. Many children's parties are decorated with balloons. While most balloons are round, they come in many sizes and shapes. Balloon artists twist long, thin balloons together to form animals, hats, and other items, and Mylar balloons are made from a kind of thin, metallic paper. Much larger balloons include hot air balloons and weather balloons. In the 1500s, balloon was a game played with a leather ball, from the Italian pallone, "large ball."

Example Sentences

By the end of June, the deficit could balloon to 900 million barrels.

From Barron's • Mar. 27, 2026

"With StepChange, it's just keeping track of one balloon," she said.

From BBC • Mar. 25, 2026

This allows events to balloon beyond our comprehension, and may be preventing us from stopping this insanity.

From Salon • Mar. 25, 2026

I had started going through menopause, so in the first or second season, I kind of blew up like a little balloon.

From Los Angeles Times • Mar. 24, 2026

“I’ll put down in a clearing in the woods, if I can,” the admiral said, frantically letting air out of the balloon until they were skimming the treetops.

From "The Long-Lost Home" by Maryrose Wood

Related Words

• enlarge
• expand
• inflate
• swell