Stac Dhòmnuill Chaim, or Stac Dhòmhnaill Chaim, is a fortified promontory located near Mangursta (or Mangersta, Scottish Gaelic: Mangarstadh) on the Isle of Lewis in the Outer Hebrides of Scotland. The stack and its surrounding site is listed and protected as a scheduled monument, one of about 8,000 sites currently protected in Scotland. The site of the stack is located at grid reference NB00223152. The site is named after Donald Cam Macaulay, the early 17th century hero of the Macaulays of Uig. The site was documented in the late 19th century, but today it is considered inaccessible.