This is the 2177th most frequent Russian word.
воздушным
"Воздушным" means "airborne" or "airy" in English.
The word 'воздушным' is used as an adjective agreeing with the noun 'шаром', forming the phrase 'воздушным шаром', which means 'with a hot air balloon'.
Воздушным шаром можно подняться в небо.
With a hot air balloon, one can ascend to the sky.
Here, 'воздушным' is used metaphorically to describe the dress as light and breezy, which is being played with by the wind.
Её воздушным платьем играл летний ветер.
The summer wind played with her airy dress.
In this sentence, 'воздушным' describes the space as open, light, and airy, enhancing the sense of spaciousness in the room.