Mac Ildoon - Irish / Mheic Maol Duin - (Chief of the fort.) A Sept / Family branch, who had their territory in Co. Armagh in the south - east of the Ulster Province.

Mac Ilduff - Irish / Mheic Giolla Dhuibh - dubh / black - haired. A Sept / Family branch,who had their territory in Co. Cavan in Southern Ulster who were also known as Duff in Co. Tyrone in Central Ulster.

Mac Ilgorm - Irish / Mheic Giolla Ghuirm - gorm / blue. A Sept / Family branch, who had their territory in the the north - east of the Ulster Province.

Mac Ilhagga. Gaelic / Mheic Giolla Chairge. Highland Scottish origins. They were in Co. Antrim and Co. Derry in the north - east of the Ulster Province. Mac Elhargy, Mac Ilhargy and Maharg were used as variants.

Mac Ilhatton - Irish / Mheic Giolla Chatain (Descended from a devotee of St. Catan) A Sept / Family branch, who had their territory in the north of Co. Antrim and Co. Derry in the north - east of the Ulster Province. Some also changed to Mac Hatton, Mac Clatton, Macklehatton and Hatton, which see.

Mac Ilholm - Irish / Mheic Giolla Choluim. Previously Mheic Giolla Chalma originally anglicized as Mac Gillecolme. A Sept / Family branch, who had their territory in the north of Co. Fermanagh in the south - west of the Ulster  Province and nearby in the west of Co. Tyrone in Central Ulster.

Mac Ilhome. See - Mac Elhone.

Mac Ilhoyle - Irish / Mheic Giolla Comhghaill. (Descended from a follower of St. Comgall) A Sept / Family branch, who had their territory in Co. Donegal and Co. Monaghan in the Ulster Province. Also see Coyle and Woods.

Mac Ilesher - Irish / Mheic Giolla Ghlais - glas / green. A Sept / Family branch, who had their territory in Co. Fermanagh in the south - west of the Ulster Province. Now changed mostly to Green and Greene. Mac Alesher /-Irish - Mheic Giolla Laisir is used as a synonym.

Mac Ilravy or Mac Elreavy - Irish / Mheic Giolla Riabhaigh. Used in the north of the Ulster Province. See Mac Kilrea.

Mac Ilveen or Mac Elveen or Mac Kilveen - Irish / Mheic Giolla Mhin - min / gentle. A Sept / Family branch, who had their territory in Co. Down in the south - east of the Ulster Province.

Mac Ilwaine or Mac Elwain or Mac Kilbane -  Irish / Mheic Giolla Bhain - ban / white. A Heremonian Ui Cobhthaigh Dal Cuinn Ui Fiachrach Sept / Family branch, who had their territory in Co. Sligo in the north - west of the Connacht Province where it was also anglicized as Mac Kilbane, which see. Ancestors - *87.Fiachra the original 2nd King of Connacht (Ui Fiachrach), *86.Eochy "Mugmedon" the 124th King of Tara / Ireland.

Mac Ilwaine. May be of Scottish origins in the Ulster Province from Mac Ilvaine, which see, or another form of Mac Ilveen, which see.

Mac Ilwraith - Irish / Mheic Giolla Riabhaigh. See - Mac Kilrea.