Yes, TURNTABLES is a Scrabble word!

Letter values in Scrabble US: T 1, U 1, R 1, N 1, T 1, A 1, B 3, L 1, E 1, S 1.

Is it a valid word?

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

a circular horizontal platform that rotates a phonograph record while it is being played
a revolving tray placed on a dining table
a rotatable platform with a track; used to turn locomotives and cars

Also: lazy susan.