Suingean
SUINGEAN—XI—Singen, Singin, St. John; Norman 'de St. Jehan,' 'de St. Jean,' i.e., of St. John's, a common French place-name; an early Norman surname in Ireland. The family settled in Wexford, Kilkenny and Tipperary. Thomas de St. John was sheriff of Tipperary in 1296.
Alphabetical Index to Irish Surnames