Yes, ECCHYMOSES is a Scrabble word!

Letter values in Scrabble US: E 1, C 3, C 3, H 4, Y 4, M 3, O 1, S 1, E 1, S 1.

Is it a valid word?

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

the purple or black-and-blue area resulting from a bruise
the escape of blood from ruptured blood vessels into the surrounding tissue to form a purple or black-and-blue spot on the skin