Yes, cox is a Scrabble word!
...and is worth 12 points in Scrabble, and 13 points in Words with Friends
cox
Verb
1. Act as the coxswain, in a boat race
Noun
1. Either of two related enzymes that control the production of prostaglandins and are blocked by aspirin
2. The helmsman of a ship's boat or a racing crew
What Scrabble words can I make with the letters in cox?
2 Letter Words