Yes, CABARET is a Scrabble word!

Letter values in Scrabble US: C 3, A 1, B 3, A 1, R 1, E 1, T 1.

Is it a valid word?

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

a spot that is open late at night and that provides entertainment (as singers or dancers) as well as dancing and food and drink
a series of acts at a night club

Also: night club, floor show.