Yes, DEFORMATION is a Scrabble word!

Letter values in Scrabble US: D 2, E 1, F 4, O 1, R 1, M 3, A 1, T 1, I 1, O 1, N 1.

Is it a valid word?

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

a change for the worse
alteration in the shape or dimensions of an object as a result of the application of stress to it
the act of twisting or deforming the shape of something (e.g., yourself)