clef

clef, in music: see musical notation.

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clef

(French; “key” )

Musical notation symbol at the beginning of a staff to indicate the pitch of the notes on the staff. Clefs were originally letters, identifying letter-named pitches, that were affixed to one or more of the staff's lines (thus providing a “key” to their identity). Knowing the identity of a single line permitted the musician to identify all the other lines and spaces above and below. Clefs were first regularly used in the 12th century. The Gothic letter forms of G and F evolved into the modern treble and bass clefs, respectively; the letter C evolved into the rarer alto, tenor, baritone, and soprano clefs.

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CLEF

(Commercial Licensed Evaluation Facility) A facility licensed by the U.K. government that performs formal security evaluations of information technology.

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clef

Music one of several symbols placed on the left-hand side beginning of each stave indicating the pitch of the music written after it