From BiblePortal Wikipedia

Webster's Dictionary [1]

(n. pl.) A race of people of uncertain origin, who inhabited Scotland in early times.

The Nuttall Encyclopedia [2]

A race of people now believed to be of Celtic origin, that from 296 to 844 inhabited the NE. of Caledonia from the Forth to the Pentland Firth, and were divided into northern and southern by the Grampians, while the W. of the country, or Argyll, was occupied by the Dalriads or Scots from Ireland, who eventually gained the ascendency over them, to their amalgamation into one nation.