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このドアには二重ロックがついています。
This door has a double lock.
double; dual; twofold
二重の意味がある。
It has a double meaning.
二重の窓ガラス
double-pane glass
Often used to describe something that has two layers or aspects.
double (in music, e.g., double bass)
二重奏
duet
In musical contexts, it can refer to instruments or voices performing in pairs.
二重 is often used to describe physical layers (e.g., double-pane windows) or abstract concepts (e.g., double meanings).
When used as a prefix (二重の), it modifies nouns to indicate they have two layers or aspects.
Combination of 二 (two) and 重 (layer, fold).
Can be used as a noun or as a prefix (二重の) to describe something with two layers or aspects.