Clancy is an Irish name coming from the Gaelic Mac Fhlannchaidh/Mac Fhlannchadha, meaning "Son of the red/ruddy warrior" (Mac being for sons, Ní Fhlannchaidh/Ní Fhlannchadha would be for daughters),[1][2] or as a hypocorism for Clarence.
The surname originated from two different families, one in Thomond and one in the present day County Leitrim.
[2] Notable people with the name include: