Yes, MATINGS is a Scrabble word!

Letter values in Scrabble US: M 3, A 1, T 1, I 1, N 1, G 2, S 1.

Is it a valid word?

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

engage in sexual intercourse
bring two objects, ideas, or people together
place an opponent's king under an attack from which it cannot escape and thus ending the game
twist together or entwine into a confusing mass
change texture so as to become matted and felt-like

Also: sexual union, felt up, mat up, matt-up, matte up.