Gaffney is a surname common to the Cavan, Irelan area, and now spread across the UK and the British Isles. Gaffney comes from the Gaelic septs of Ó Gamhna, Mac Conghamhna and Ó Caibheanaigh. Gaffney more commonly doesn't appear with the Gaelic prefixes of O' or Mc but there have been Gaffneys recorded with either of the Gaelic prefixes. People with the name Gaffney include: