Is OS a valid Scrabble word?
YES — OS is a valid Scrabble word 2 points
Scrabble® and Words With Friends® points for OS
OS is a valid Scrabble US/CAN word worth 2 points:
O1S1
OS is valid in Scrabble UK (World) —
O1S1
OS is a valid Words With Friends word worth 2 points:
O1S1