A balloon made of rubber, latex, or similar material used as a toy or decoration (party balloons, toy balloons).
子どもたちが風船で遊んでいる。
Children are playing with balloons.
誕生日パーティーの会場はカラフルな風船で飾られていた。
The birthday party venue was decorated with colorful balloons.
風船を膨らませるときは口だけでなくポンプを使うと楽だ。
When inflating balloons, it's easier to use a pump rather than just your mouth.
A dated/older term for an air or hot-air balloon (historical usage for larger balloons).
昔の絵には空に浮かぶ風船が描かれていることがある。
Old paintings sometimes depict balloons floating in the sky.
博物館の説明に、当時は大型の風船が軍事や観測に使われたと書かれていた。
The museum description said that at the time large balloons were used for military or observation purposes.