The definition of a balloon is material such as rubber, silk or plastic which can be filled with air or gas.(noun)
An example of a balloon is a blimp.
To balloon is defined as to expand in size or to increase quickly.(verb)
To balloon means to ride in something powered by gas-filled silk or plastic.(verb)
An example of someone who may balloon is a person flying a hot air balloon.
See balloon in Webster's New World College Dictionary
Origin: Fr ballon, altered (after balle) < It pallone, large ball < palla, ball < Langobardic *palla (OHG balla), ball
See balloon in American Heritage Dictionary 4
Origin: French ballon
Origin: , from Italian dialectal ballone
Origin: , augmentative of balla, ball
Origin: , of Germanic origin; see bhel-2 in Indo-European roots.
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