Yes, TRANSFIGURATION is a Scrabble word!

Letter values in Scrabble US: T 1, R 1, A 1, N 1, S 1, F 4, I 1, G 2, U 1, R 1, A 1, T 1, I 1, O 1, N 1.

Is it a valid word?

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

(Christianity) a church festival held in commemoration of the Transfiguration of Jesus
(New Testament) the sudden emanation of radiance from the person of Jesus
a striking change in appearance or character or circumstances
the act of transforming so as to exalt or glorify

Also: transfiguration day, august 6, transfiguration of jesus.