ダブり

名簿にダブりがないか確認してください。

Please check the list for duplicates.

カードのダブりを友達と交換した。

I traded my duplicate cards with a friend.

予定のダブりに気づかず、約束を二つ入れてしまった。

I didn't notice the scheduling overlap and made two appointments at once.

彼はダブりだから、同じクラスでも一つ年上だ。

He repeated a year, so he's a year older even though we're in the same class.

単位が足りなくてダブりが決まった。

I didn't have enough credits, so I'm being held back a year.

ダブりの先輩がゼミに入ってきた。

A senior who had repeated a year joined our seminar.