Yes, ANCIENT is a Scrabble word!

Letter values in Scrabble US: A 1, N 1, C 3, I 1, E 1, N 1, T 1.

Is it a valid word?

ANCIENT is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

belonging to times long past especially of the historical period before the fall of the Western Roman Empire
very old