Yes, tart is a Scrabble word!
...and is worth 4 points in Scrabble, and 4 points in Words with Friends
tart
Adjective
1. Tasting sour like a lemon
2. Harsh
Noun
1. A woman who engages in sexual intercourse for money
2. A small open pie with a fruit filling
3. A pastry cup with a filling of fruit or custard and no top crust
What Scrabble words can I make with the letters in tart?
3 Letter Words
2 Letter Words