The term 'Treble or Bass' refers to the two main types of clefs used in music notation. The treble CLEF is also known as the G CLEF, and is used for higher pitched instruments such as the violin, flute, and oboe. The bass CLEF is also known as the F CLEF, and is used for lower pitched instruments such as the cello, bassoon, and trombone. The crossword solutions for this term are CLEF (4 letters) and VIOL (4 letters). The word CLEF is an abbreviation for CLEF, which is a symbol used in musical notation to indicate the pitch of the notes written on the staff. The word VIOL is an abbreviation for the stringed instrument, the violin.