The Nuttall Encyclopedia
A heap of stones often, though not always, loosely thrown together, generally by way of a sepulchral monument, and it would seem sometimes in execration of some foul deed.
Wood, James, ed. Entry for 'Cairn'. The Nuttall Encyclopedia. https://www.studylight.org/encyclopedias/eng/nut/c/cairn.html. Frederick Warne & Co Ltd. London. 1900.