noun
horizontally striped shirt
A shirt with horizontal stripes, typically a casual long-sleeve T-shirt or cut-and-sewn top. The term comes from 'border' referring to the stripe pattern.
彼は今日、青と白のボーダーシャツを着ている。
He is wearing a blue and white striped shirt today.
Variant with a middle dot; less common in everyday writing.
From English 'border' + 'shirt', referring to the striped pattern.