Tadc mac Briain

Tadc mac Briain (died 1023) was a son of Brian Boru by his wife Echrad. After his father's death at Clontarf in 1014, he was a leading contender for the kingship of Munster, rivalling his half-brother Donnchad mac Briain.

By his wife Mór he fathered Toirdelbach Ua Briain, who later became king of Munster and one of Ireland's most powerful kings. Tadc was assassinated in 1023 at Donnchad's instigation.