The term 'scale interval' refers to the distance between two notes in a musical scale. The three crossword solutions for this term are semitone (8 letters), OCTAVE (6 letters), and STEP (4 letters). A semitone is the smallest interval in Western music, and is the distance between two adjacent notes on a piano keyboard. An OCTAVE is an interval of eight notes, and is the distance between two notes with the same letter name. A STEP is an interval of two notes, and is the distance between two notes with the same letter name but one note higher.