Yes, nans is a Scrabble word!
...and is worth 4 points in Scrabble, and 6 points in Words with Friends
nans
Noun
1. Your grandmother
2. The mother of your father or mother
3. A river of western Thailand flowing southward to join the Ping River to form the Chao Phraya
4. Leavened bread baked in a clay oven in India; usually shaped like a teardrop
What Scrabble words can I make with the letters in nans?
3 Letter Words
2 Letter Words