Yes, FOMENTATION is a Scrabble word!

Letter values in Scrabble US: F 4, O 1, M 3, E 1, N 1, T 1, A 1, T 1, I 1, O 1, N 1.

Is it a valid word?

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

a substance used as a warm moist medicinal compress or poultice
application of warm wet coverings to a part of the body to relieve pain and inflammation
deliberate and intentional triggering (of trouble or discord)