Bémol

Bémol is the musical term used in French and several Romance languages to denote the flat, a pitch that is one semitone lower than the natural note. It is represented in notation by the flat sign ♭, which, when placed before a note, lowers that pitch by one semitone. Flats also appear in key signatures to indicate a recurring lowering of all instances of a given note within a piece.

The flat sign evolved from a stylized letter form and has become a standard symbol in Western music notation. The term bémol is widely used in French, while many other languages use bemol or similar forms derived from the same root, often tracing back to Italian bemolle. In practice, the concept is universal across Western notation: a note with a flat is slightly lower in pitch than its natural counterpart.

Enharmonic relationships are common with flats. For example, B♭ (the note B flattened) is enharmonic with A♯ (A sharp). In French musical nomenclature, the note B natural is called “si,” and the flattened form is “si bémol.” Flats feature prominently in key signatures—such as B♭ major, which includes B♭ and E♭—as well as as accidentals applied to individual notes.

Double flats exist as well, indicated as “bémol double” in some languages, used to lower a note by two semitones. The concept of the bémol is foundational to pitch organization, harmony, and tuning in Western music.