Scots cairn, from Gaelic càrn, has denoted a pile of stones since the Middle Ages, as demonstrated by this quotation from the Rental Book of the Cistercian Abbey of Cupar-Angus (1557):
The croft of land callit the well medow...is devidit be carnis of stanis.
In Scots it can also indicate a stony hill. Such areas are not always conducive to cultivation, as in this Banffshire quotation from the Scottish National Dictionary:
His placie lay at the fit o' the cairn o' the Ord, an' wiz maistly gey peer grun.