Tritone
In music theory, a tritone is a musical interval spanning three whole tones. For instance, the interval from F to the B above it (in short, F–B) is a tritone as it can be decomposed into the three adjacent whole tones F–G, G–A, and A–B. In 12-tone-equal temperament, the tritone divides the octave (which is 12 semitones or 1200 cents) exactly in half, making it six semitones, or 600 cents.