also: ヘアーバンド
noun
A band worn around the head, often for fashion or to keep hair in place. Can refer to both soft fabric bands and rigid plastic ones.
運動するときはヘアバンドをしている。
I wear a headband when I exercise.
彼女は花柄のヘアバンドをつけていた。
She was wearing a floral-patterned hair band.
カチューシャ typically refers to a rigid, U-shaped headband (often plastic), while ヘアバンド is broader and includes soft fabric bands.
Loanword from English 'hair band'.