Yes, DEHISCENCE is a Scrabble word!

Letter values in Scrabble US: D 2, E 1, H 4, I 1, S 1, C 3, E 1, N 1, C 3, E 1.

Is it a valid word?

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

(biology) release of material by splitting open of an organ or tissue; the natural bursting open at maturity of a fruit or other reproductive body to release seeds or spores or the bursting open of a surgically closed wound