Melaghlin Reagh Ua Seachnasaigh

Melaghlin Reagh Ua Seachnasaigh (died 1179) was an Irish Chief of the Name.
Ó Seachnasaigh was the first bearer of the surname to be listed as of Cenél Áeda na hEchtge. However, the territory seems to have been contended with the Ó Cathail family. The Annals of the Four Masters record, "sub anno" 1179:
"Melaghlin Reagh O'Shaughnessy, Lord of half the territory of Kinelea, was killed by the son of Donough O'Cahill."
He was a descendant of Seachnasach mac Donnchadh.