What does "mort" mean?

Additional senses

1. 2.A note or series of notes sounded on a horn at the death of game. The sportsman then sounded a treble mort. Sir W. Scott.
2. 3.The skin of a sheep or lamb that has died of disease. [Prov. Eng. & Scot.] Mort cloth, the pall spread over a coffin; black cloth indicative or mourning; funeral hangings. Carlyle. -- Mort stone, a large stone by the wayside on which the bearers rest a coffin. [Eng.] H. Taylor.