What is "soghain"

The Soghain were a people of ancient Ireland. Dubhaltach Mac Fhirbhisigh identified them as part of a larger group called the Cruithin, and stated of them: Of the Cruithin of Ireland are the Dál Araidhi (Dál nAraidi), the seven Lóigisi of Leinster, the seven Soghain of Ireland, and every Conaille (see Conaille Muirtheimne) that is in Ireland.