Lament: A mournful piece, either meant to be played at a funeral, or to commemorate a death.
Landini Cadence: The melodic cadence that moves in the sequence 7-6-8, used primarily by Francesco Landini, and later by other composers.
Leading Tone: The seventh degree of the diatonic scale, when it is only a half-step below the tonic. It is called "leading" because it gives the feeling of wanting to move up a half-step toward the tonic.
Leap: the movement of a single musical line by more than a second at a time.
Ledger Lines: Lines written above or below the staff to help indicate the correct pitches for notes written outside of it.
Leitmotif: "Leading Motive". Use of a musical phrase to identify with a certain person, place or thing in a dramatic work, especially an opera, usually repeated every time its referrant appeared in the work.
Lied/Lieder: A German art song, usually those of the Romantic or Classical eras.
Litany: A set of prayers recited by a leader alternating with responses by the congregation, often set in plainsong form.
Locrian Mode: A mode whose scale pattern is that of playing B to B on the white keys of a piano. While this mode theoretically existed in medieval times, it was never used.
Lullaby: A cradle song.
Lydian Mode: A medieval mode whose scale pattern is that of playing F to F on the white keys of a piano.
Lyric: 1. The words to a song. 2. In a singing and melodious manner.
Lyric Soprano: A female singer with a slightly higher range than a Dramatic Soprano.
Lyric Tenor: A male singer with a slightly higher range than a Dramatic Tenor.