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B-flat major (uncountable)

(music) The major key with B-flat as its tonic, with the notes B♭, C, D, E♭, F, G, and A, the key signature of which has two flats.

${\key bes \major bes c' d' es' f' g' a' bes'2}$
(music) The major chord with a root of B-flat.

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