Yes, REVERSES is a Scrabble word!

Letter values in Scrabble US: R 1, E 1, V 4, E 1, R 1, S 1, E 1, S 1.

Is it a valid word?

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

a relation of direct opposition
the gears by which the motion of a machine can be reversed
an unfortunate happening that hinders or impedes; something that is thwarting or frustrating
the side of a coin or medal that does not bear the principal design
(American football) a running play in which a back running in one direction hands the ball to a back running in the opposite direction
turning in the opposite direction
a lapel on a woman's garment; turned back to show the reverse side

Also: reverse gear, black eye, change by reversal, turn back.