Gael
"Gwyddel", meaning 'raider', was initially the name given to the Scots of Dalriada by the Brythonic (Old Welsh) speaking tribes when they were expanding their kingdom into in Strathclyde . As stated in the Declaration of Arbroath, "The Britons they first drove out". "Gwyddel" (Old Welsh), "Gaidheal" (Scots Gaelic) and later Anglicised into Gael. 
Scot and Gael were synonymous until the 15th century.