name McCuin family name. Variations found include O'Quinn, Quin, Quinn, Quine, MacQuin, MacQuinn, McQuin, McQuinn, MacCuin, Cuinn, Cuin and many more. First found in county Longford where they were Lords of Muintir Gillagain. The O'Quinns and MacQuinns (and all of the spelling variables derived from these) were descended from Conn, who