Yes, BASTILLE is a Scrabble word!

Letter values in Scrabble US: B 3, A 1, S 1, T 1, I 1, L 1, L 1, E 1.

Is it a valid word?

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

a fortress built in Paris in the 14th century and used as a prison in the 17th and 18th centuries; it was destroyed July 14, 1789 at the start of the French Revolution
a jail or prison (especially one that is run in a tyrannical manner)