Scottish Highlander (4)
I believe the answer is:
gael
'scottish highlander' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for gael that I've seen before include "Celt of Ireland, the Scottish Highlands and the IOM" , "Celtic language speaker" , "Highland Scot" , "Irish speaker?" , "Scottish highlander" .)