Yes, SATINWOOD is a Scrabble word!

Letter values in Scrabble US: S 1, A 1, T 1, I 1, N 1, W 4, O 1, O 1, D 2.

Is it a valid word?

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

West Indian tree with smooth lustrous and slightly oily wood
hard yellowish wood of a satinwood tree having a satiny luster; used for fine cabinetwork and tools
East Indian tree with valuable hard lustrous yellowish wood;

Also: west indian satinwood, zanthoxylum flavum, satinwood tree, chloroxylon swietenia.