noun
A musical symbol used to indicate which notes are represented by the lines and spaces on a stave. Placing a clef on a particular line of a stave stands for assigning a particular note to one of the five lines. Then, the line becomes a reference point by which the names of the other notes on the stave are determined.
See also: alto clef, bar line, bass clef, C-clefs, double bar, F-clefs, G-clefs, tenor clef, treble clef