Muirchertach (modern spelling: Muircheartach, anglicised as Murtagh) is an Irish language male given name meaning "mariner". Muirchertach was borne by several figures from legend and history, including:
Muirchertach mac Ercae, great-grandson of Niall of the Nine Hostages and High King of Ireland
Muirchertach mac Néill, 10th-century king of Cenél nEógain
Muircheartach Ua Briain, 12th-century High King of Ireland
Muirchertach Mac Lochlainn, 12th-century king of Cenél nEógain
Muirchertach mac Maelruanaidh Mor, obscure king of Moylurg
