planxty
An Irish or Welsh melody for the harp, sometimes of a mournful character.
Dr. Arne. Owenson, who was a handsome young man with a commanding presence, was bitten by a mania for the stage, but failed to make much impression as an actor, though he sang, and danced an Irish planxty in the character of Teague with great success.
Where it comes from
Compare Latin planxī (“to have mourned ...”), planctus (“a lament or dirge”), and plangere (“to mourn aloud”).
Adapted from the Wiktionary entry planxty (CC BY-SA 4.0).