the name of the staff used for higher pitches
Staff (music) The absolute pitch of each line of a non-percussive staff is indicated by the placement of a clef symbol at the appropriate vertical position on the left-hand side of the staff (possibly modified by conventions for specific instruments). For example, the treble clef, also known as the G clef, is placed on the second line (counting upwards), fixing that line as the pitch first G above 'middle C'.