The hill's Gaelic name translates as the Peak of the Black Chest or Coffin. The meaning of the name is unsure but it is thought to refer to an unusual deep rocky hollow near the summit which lies between the main ridge and a false crest. This can be dangerous in mist or snow conditions. Other sources say that the name refers to the deep hollow of the Allt Dearg on the hills south west slope. The mountain should not be confused with another Munro called Ciste Dhubh which lies just 7 km to the east.