The name “Carnagat” (Carn na gcat? Cathair na gcat?) according to local tradition arose from the fact that the cairn was the haunt of wild cats. I have once heard it called “Carraig na gcat” by an old country woman, who corrected my referring to it as “Carnagat,” but the latter is the usual name. Local folklore has it that these fairy cats were wont to steal the corn from the harvesters and convey it hither to their stronghold – the chief trysting place of all the fairy bands of the country round!
From Royal Society of Antiquaries of Ireland JRSAI 52 (1922), Carnagat, by Winifred Wulff, member (read 5 July, 1921)