enharmonic

adjective

• relating to or denoting notes which are the same in pitch (in modern tuning) though bearing different names (e.g. F sharp and G flat or B and C flat): double flats and double sharps are replaced by their enharmonic equivalents in harp music
• of or having intervals smaller than a semitone (e.g. between notes such as F sharp and G flat, in systems of tuning which distinguish them).