1.
headband, hair band
A curved band worn over the head to hold hair back. In English this is called a headband or Alice band.
Etymology
Named after the character Katyusha (カチューシャ) in Tolstoy's novel "Resurrection," who wore a headband in a famous early 20th-century Japanese stage adaptation. The name stuck as the Japanese word for this type of hair accessory.
Usage
カチューシャ specifically refers to a rigid or semi-rigid curved headband, not a soft elastic band (ヘアバンド) or a hair tie (ヘアゴム).