D minor
Refers to the key of D minor in Western music theory. Used in contexts such as key signatures, compositions, and music analysis.
この曲はニ短調で書かれている。
This piece is written in D minor.
D sharp minor
Compound of ニ (the note D) and 短調 (minor key). The note name ニ comes from the Japanese iroha ordering assigned to the Western scale degrees.