Yes, GENERALIZES is a Scrabble word!

Letter values in Scrabble US: G 2, E 1, N 1, E 1, R 1, A 1, L 1, I 1, Z 10, E 1, S 1.

Is it a valid word?

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

draw from specific cases for more general cases
speak or write in generalities
cater to popular taste to make popular and present to the general public; bring into general or common use
become systemic and spread throughout the body