Yes, DEVIATIONS is a Scrabble word!

Letter values in Scrabble US: D 2, E 1, V 4, I 1, A 1, T 1, I 1, O 1, N 1, S 1.

Is it a valid word?

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

a variation that deviates from the standard or norm
the difference between an observed value and the expected value of a variable or function
the error of a compass due to local magnetic disturbances
deviate behavior
a turning aside (of your course or attention or concern)