key signature

American  

noun

Music.

1. (in notation) the group of sharps or flats placed after the clef to indicate the tonality of the music following.

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key signature British  

noun

1. music a group of sharps or flats appearing at the beginning of each stave line to indicate the key in which a piece, section, etc, is to be performed

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Etymology

Origin of key signature

First recorded in 1870–75

Example Sentences

Others found fault with the way the U of R group measured the material’s magnetic behavior, a key signature of superconductivity.

From Science Magazine • Mar. 8, 2023

Chunky bracelets and earrings rounded out the looks, a key signature of the designer.

From Reuters • Sep. 27, 2022

Water is considered a key signature of life beyond Earth, after all.

From Salon • Jul. 13, 2022

Things like dynamics, key signature, time signature, and a song’s overall structure can be taken in by an experienced musician almost intuitively.

From The Verge • Nov. 18, 2020

The most important symbols on the staff, the clef symbol, key signature and time signature, appear at the beginning of the staff.

From "Understanding Basic Music Theory" by Catherine Schmidt-Jones and Russel Jones