The property Chord.commonName returns the most common name associated with a chord. The returned string is from the table chord.tables.tnIndexToChordInfo and has e.g. the form dominant seventh chord On the other side there is the table harmony.CHORD_TYPES where the chord is named dominant-seventh. CHORD_TYPES is used by class Harmony. tnIndexToChordInfo is used by class Chord. Is there a way in music21 to get the representation in CHORD_TYPES having the tnIndexToChordInfo? Use case: I use Chords generated from RomanNumeral in a Scale and want to display the shortname in the lyric. The commonName is too long. k = scale.MelodicMinorScale('c') rn = roman.RomanNumeral('V7', k, caseMatters=False) c = chord.Chord(rn) c.lyric = rn.figure + "\n" + rn.commonName Continue reading...