When the G-clef is placed on the second line of the staff, it is called the "treble clef". This is by far the most common clef used today, and the only G-clef still in use.
MLA Style "G clef." Webster's New World College Dictionary. 2009. Your Dictionary. 6 July 2009 <www.yourdictionary.com/g-clef> APA Style. G clef. (2009).