noun
advertising balloon
A large balloon, often tethered, used for outdoor advertising. Wasei-eigo from 'ad balloon'.
wasei-eigo (Japanese-coined English), from ad balloon
デパートの開店セールで、大きなアドバルーンが空に浮かんでいた。
At the department store's opening sale, a large advertising balloon was floating in the sky.
Rare spelling with a middle dot; the solid form is overwhelmingly more common.
Wasei-eigo from English 'ad balloon'.