Real Dictionary

treble clef
countable noun: A treble clef is a symbol that you use when writing music in order to show that the notes on the staff are above middle C.

treble clef in American English
a sign on a staff, indicating the position of G above middle C on the second line
noun: a sign that locates the G above middle C, placed on the second line of the staff, counting up; G clef

treble clef in British English
noun: the clef that establishes G a fifth above middle C as being on the second line of the staff