Seachnasach (died 711) was the 17th king of the Uí Maine.
This includes him among the Clann Comain sept of the dynasty.
During his reign Cellach mac Rogallaig won the battle of Corran, and in 710, Dluthach mac Fithcheallach, possibly a son of the previous king, "was burned."
The annals merely report his death.
This Irish biographical article is a stub.