A sequence is where a passage of music is repeated at a higher or lower level of pitch. The repeat can be an exact transposition – a real sequence or the intervals can be changed – a tonal sequence. The Oxford Dictionary of Music defines a sequence as the “more or less exact repetition of a passage at a higher or lower level of pitch”.

sequence, in music, a melodic or chordal figure repeated at a new pitch level (that is, transposed), thus unifying and developing musical material.