This is the 2341st most frequent Japanese word.
ふわふわ
Soft, fluffy, or light.
The word "ふわふわ" describes the soft and fluffy texture of the cat's fur.
猫の毛はふわふわしている。
The cat's fur is fluffy.
Here, "ふわふわ" conveys the motion of the balloon as it gently and lightly floats.
風船が空にふわふわと浮かんでいる。
The balloon is floating lightly in the sky.
In this sentence, "ふわふわ" metaphorically describes the unclear or whimsical nature of her thoughts.