The term 'Pitch Indicator' refers to a device used in music to measure the frequency of a NOTE or sound. It is composed of three components: a CLEF, a NOTE, and a gclef. A CLEF is a symbol placed at the beginning of a staff in musical notation to indicate the pitch of the notes written on it. A NOTE is a sign used in musical notation to represent the relative duration and pitch of a sound. Finally, a gclef is a CLEF that is placed on the second line of the staff, indicating that the notes written on it are higher in pitch than those written on the first line. Together, these three components form the Pitch Indicator, which is used to measure the frequency of a NOTE or sound.