O Martin / Irish - Ui Martain / A Sept - Family branch who had their territory in Co. Westmeath - North East Leinster in the 16^th Century.

Martin / Used to abbreviate Gilmartin.

Mac Martin or Gilmartin / Irish - Mheic Ghiolla Mhartain - descended from a son of the follower of St. Martin / A Heremonian Dal Cuinn Sept - Family branch of the "Northern" Ui Niaill Tuath - Family region whose territory was at Clogher in Co. Tyrone - Central Ulster and in Co. Fermanagh - North West Ulster / They were driven out to Co. Sligo & Co. Leitrim - Northern Connacht. *88.Eogan.

Martin / Anglo Norman origins / They came with the Anglo - Norman Invasion and ruled as Kings around Bally na Hinch Loch and Connemara Loch, in Co. Galway - Southern Connacht / They were one of the 14 "foreign" Tribes of Galway / Charles 11 after the English Restoration gave them 250,000 acres of the land of Ui Briuin Seola O Flahertys who where then the Kings of West - Iar Connacht at Ballynahinch / The Martins were then one of the wealthiest families in Co. Galway up until the Great Famine with their main residence at Ross House beside the shore of Ross Lake / During the Great Famine Thomas Martin & Mary his daughter spent the Family fortune on trying to give relief, which bankrupted them / Their family home still exists at Ballynahinch.

O Marum / May be the Irish - Ui Marum /  A Sept - Family branch who had their territory in the Heremonian Cu Corb kingdom of Ossory in Co. Kilkenny - Western Leinster in 1690 / Kieran Marum was one of the Bishops of Ossory.

Marward / English Barons / They were in Co. Meath - North East Leinster.

Massey / English Barons they were at Clarina in Co. Limerick - North West Munster.

Matchett /

Mateer / Used for Mac Ateer, which see.

Mac Math / Highland Scottish origins / A Sept - Family branch of the Mathesons who were in UIster in the 17th Century / Known as Mac Meath in Co. Monaghan - Southern Ulster / Mac Magh & Mac Maugh were also used as variants / See also Mac Mawe.

O Mathain / Irish - Ui Mathain / A Sept - Family branch who had their territory in Co. Longford - North West Leinster.

Mather or Mathers / mather - mower / English origins / They came from Yorkshire known there as Mather and known as such in Co. Dublin - Mid Eastern Leinster since the 17th Century and later in Co. Armagh - South East Ulster / Mathers used in Ulster / Also changed to Mathews in Co. Down - South East Ulster.

Matheson /  See Mac Math.

Mathew / English origins / Fr. Theobold Mathew was from Thomastown in Co. Tipperary - Northern Munster.

Matthews / English origins / They were in Ulster and Co. Louth - North East Leinster / Used also as synonym for Mac Mahon, which see, there.

Maturin / French Huguenot origins /

Maude / They were among the Irish speakers in the Connemara in the west of Co. Galway - Southern Connacht.

Maude / English origins / They were in Co. Kilkenny - Western Leinster in the 17th Century.

Mac Maugh / See Mac Math.

O Maughan / Used as a variant for Maghan & Mohan, which see.

Maume / Used for Maune, which see.