triangular headscarf; triangle headband; triangular bandana
A triangular piece of cloth worn on the head, often tied under the chin. Commonly associated with traditional workwear, homemakers, or historical settings.
My grandmother always wore a triangular headscarf when cleaning.
In period dramas, town girls often wear triangular headscarves.
バンダナ is a modern bandana, often square and tied in various styles, while 三角頭巾 specifically refers to a triangular cloth tied under the chin, with a more traditional or domestic image.
頭巾 is a general term for a hood or headscarf; 三角頭巾 specifies the triangular shape and typical chin-tie style.
Compound of 三角 (さんかく, 'triangle') and 頭巾 (ずきん, 'hood, headscarf'). The exact historical origin is uncertain, but the term describes the shape and function of the cloth.