Irish
1) An ethnic group consisting of the indigenous people of the island of Ireland as well as the descendants of those people who immigrated abroad.

2) A citizen of a Republic on some God-forsaken waterlogged island in the north Atlantic who can't seem to wrap his head around the fact that the word "Irish" can denote either an ethnicity or a nationality and one does not have to belong to one group to belong to the other.
Irish dude from Boston: OK, I'll try to explain one last time. Here, look at this Venn diagram. It has bright colors and everything. After we get done, you can even use it as a coloring book. There, that's a good boy!

Irish dude from Dublin: *stomps feet, sticks fingers in ears and clenches teeth* *Feck you, stupid yank, you're not Irish and never will be! Feck you, stupid yank, you're not Irish and never will be! Feck you, stupid yank, you're not Irish and never will be! Feck you, stupid yank, you're not Irish and never will be! Feck you, stupid yank, you're not Irish and never will be! Feck you, stupid yank, you're not Irish and never will be! Feck you, stupid yank, you're not Irish and never will be! .....

Irish dude from Boston: No wonder my ancestors left that place...