Yes, roan is a Scrabble word!
...and is worth 4 points in Scrabble, and 5 points in Words with Friends
roan
Adjective
1. (used of especially horses) having a brownish coat thickly sprinkled with white or grey
Noun
1. A soft sheepskin leather that is colored and finished to resemble morocco; used in bookbinding
2. A horse having a brownish coat thickly sprinkled with white or gray
What Scrabble words can I make with the letters in roan?
3 Letter Words
2 Letter Words