Yes, EXPLICIT is a Scrabble word!

Letter values in Scrabble US: E 1, X 8, P 3, L 1, I 1, C 3, I 1, T 1.

Is it a valid word?

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

precisely and clearly expressed or readily observable; leaving nothing to implication
in accordance with fact or the primary meaning of a term