1A sign placed before a musical note to indicate that it is to be lowered two semitones.
（加在音符前的）重降号（）
Example sentencesExamples
The sharp raises the note before which it is placed by one semitone; the flat lowers it by one semitone; the double sharp and double flat respectively raise and lower it by a whole tone; the natural cancels any other accidental.
1.1A musical note marked by a double flat or lowered two semitones.
Example sentencesExamples
Gurney knows it well - witness the opening line of ‘Sleep’ (D flat-F; D flat-B double flat).
Definition of double flat in US English:
double flat
nounˈdəbəl flat
1A sign placed before a musical note to indicate that it is to be lowered two semitones.
（加在音符前的）重降号（）
Example sentencesExamples
The sharp raises the note before which it is placed by one semitone; the flat lowers it by one semitone; the double sharp and double flat respectively raise and lower it by a whole tone; the natural cancels any other accidental.
1.1A musical note marked by a double flat or lowered two semitones.
Example sentencesExamples
Gurney knows it well - witness the opening line of ‘Sleep’ (D flat-F; D flat-B double flat).