of those people of N Ireland descended from Scottish settlers, esp. those who emigrated to America
See Scotch-Irish in American Heritage Dictionary 4
noun In both senses also called Scots-Irish.
The people of Scotland who settled in northern Ireland or their descendants, especially those who emigrated to North America. See Usage Note at Scottish.
The variety of Scots spoken by the Scotch-Irish.
adjective
Of or relating to the Scotch-Irish or their variety of Scots.