Y-fronted

UK not-comparable

(UK) Having a Y-shaped seam, as Y-fronts do. / (UK) Wearing Y-fronts.

Japanese Meaning

Y字型の縫い目がある（Yフロントスタイルの下着に見られるデザイン） / Yフロントスタイルの下着を着用している

She packed a pair of Y-fronted briefs for the trip because they were comfortable and supportive.

彼女は旅行のために、快適でサポート力のあるY字型の縫い目があるブリーフを一枚入れた。

Sense（1）

(UK) Having a Y-shaped seam, as Y-fronts do.

Underneath he was wearing white Y-fronted underpants.

Sense（2）

(UK) Wearing Y-fronts.