The Lornak were one of the historical clans of Acamar III. During the mid-23rd century, the Lornak participated in a massacre of members of a rival clan, the Tralesta, killing all but five members of the Trelesta.
Yuta, the chosen surviving Tralesta, made it her mission in life to kill all of the Lornak. She nearly accomplished this in 2366 when she attacked Chorgan, the last living member of the Lornak clan with ties to the massacre, during negotiations between him and Sovereign Marouk. (TNG: "The Vengeance Factor")