How to say "balloon" in Japanese

Choosing the right word

バルーンCommon
nounThe katakana loanword from English. It covers balloons generally, but in practice you hear it mostly for balloons as party or event decorations, where it has a stylish, Western feel.
風船ふうせんJLPT N2approx.Common
nounThe native word for the balloon as a toy or decoration: the rubber balloon you blow up for a child, or balloons handed out at festivals or used as party decorations.
風船ふうせんが空そらに上あがっていった。↗
The balloon went up in the sky.
気球ききゅうCommon
nounThe balloon as a flying craft: hot-air balloons, weather balloons, and blimps. Use it for a balloon in the sky or a balloon ride; it is not the word for party balloons.
気球ききゅうが空そらに浮うかんでいた。↗
A balloon was floating in the air.

For balloons as toys or party decorations use 風船, with the loanword 「バルーン」 heard especially for event and decorative balloons; for balloons that fly — hot-air and weather balloons, blimps — use 気球.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

Japanese equivalents

バルーンballoon
風船ふうせんballoon (toy or decoration)
気球ききゅうballoon (hot-air, weather, etc.)
膨れ上がるふくれあがるto swell (of a budget, population, etc.)

JLPT vocabulary levels are community estimates, not official (no official lists have been published since the 2010 revision).

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