enharmonical

Adjective

enharmonic (not comparable)

1. Describing two or more identical or almost identical notes that are written differently when in different keys. (Whether they are identical and what the exact equivalences are depends on the tuning used.)
   • C sharp is enharmonic to D flat in twelve-tone equal temperament, but in most other tuning systems they are distinct pitches.
2. Of or pertaining to a tetrachord.