What term refers to the reversal of melody as if from right to left?

The term that refers to the reversal of a melody, as if played backward from right to left, is called retrograde. In retrograde, the sequence of notes in the melody is presented in reverse order, maintaining the original rhythm and articulation of the music. This technique is often used in various forms of music composition, including counterpoint and serialism, to create variations and new interpretations based on the original melodic material.

Melodic inversion, in contrast, involves altering the original melody so that the intervals are mirrored around a central pitch, rather than simply reversing the order of the notes. Serialism is a compositional technique that revolves around the use of a series of values to manipulate musical elements, and bitonality refers to the simultaneous use of two different keys or tonalities. These concepts highlight the distinctiveness of retrograde as a method of manipulating melodies uniquely.