tono-, ton-, -tonia, -tonic, -tonous, -tony

(Greek > Latin: sound, tone; that which is stretched, a stretching, a straining, a pitch of the voice, a musical note)

Having a spatial arrangement such that certain tone frequencies are transmitted along a particular portion of the structure, as in the cochlear nuclei.
tritone (s) (noun), tritones (pl)
An interval composed of three whole musical notes: The tritone derives its name from the fact that it spans three whole tones and it refers to any musical interval of six semitones.

Two tritones add up to six whole tones, or twelve semitones, which usually produce a perfect octave.