The origins of some of the surnames associated with the Cenél nEógain

The O'Neill's or Ua Néill, meaning "descendant son of Niall" not Niall of the Nine Hostages but Niall Glundubh MacAedo.

The original Gaelic meaning of Neil is unclear, but Champion or Cloud. The Anglo-Scandinavian form of the Gaelic name Niall.

 It is believed to have been adopted by the Scandinavians in the form Njal and was introduced into northern England and East Anglia by them, rather than being taken directly from Gaelic.

O'Kane from the word "cath", meaning battle.

ODevlin's hereditary sword-beares to the O'Neill's and part of the calvary. 

Maclaughlin "son of Lochlann", the Norse elements of "loch", a lake or fjord, plus "lann". Possible meaning"Son of the land of the Norse ". The MacLaughlin of Innishowen current Co. Donegal. Where the rulers of the Cenel Eoghain for many years.

Lamonts from the Norse word Ladhman meaning "Lawman" or "Lawyer" . They are said to be the descendants of Dunshleibhe O'Neill. They have various adoption of surnames including the surnames White, Black,Turner, Brown and Clements. In the 16th century the Clan Campbell slaughter the leading members of the clan Lamont. The Lamonts were also on time called Macerchar, from Fearchar, the grandfather of the first.