Yes, SHAKERS is a Scrabble word!

Letter values in Scrabble US: S 1, H 4, A 1, K 5, E 1, R 1, S 1.

Is it a valid word?

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

a celibate and communistic Christian sect in the United States
a person who wields power and influence
a member of Christian group practicing celibacy and communal living and common possession of property and separation from the world
a container in which something can be shaken

Also: united society of believers in christ's second appearing, mover and shaker.