Galmoy (Irish: Gabhalmhaigh, meaning 'plain of the Ghabhal [River Goul]')[1][3] is a barony in the north western part of County Kilkenny, Ireland.

The name of Galmoy, in Irish Gabhalmhaigh, means "plain of the Branch, or Ghabhal" (River Goul).

[7][8] According to O'Heerin's Topographical Poem (1420)[8] at the time of the Norman invasion the area was the territory of the clan called the Ua Bróithe (O'Brophy) of Mag Sédna.

In a 1247 feodary, Stephen Archid[ekne] holds 21⁄2 knights' fees in Ganelomey (also known at the time as Gauleme) in the Calendar of Patent Rolls.

[3][9] In the 1324 feodary, Raymond le Ercedekne, son of Richard, held the lands of Gavelmoy, in the barony of Galmoy.

[7] By the 19th century these were restructured into the baronies of Callan, Crannagh, Fassadinin, Galmoy, Gowran, Ida, Iverk, Kells, Knocktopher, and Shillelogher.