An indication of the key of a composition, giving the number of sharps or flats in the corresponding scale
The key signatures of D major and b minor both have two sharps.
(Muzik) The group of sharps or flats placed to the right of the clef on a staff to identify the key
n. Music The group of sharps or flats placed to the right of the clef on a staff to identify the key. a set of marks at the beginning of a line of written music to show which key it is in