Yes, ziti is a Scrabble word!
...and is worth 13 points in Scrabble, and 13 points in Words with Friends
ziti
Noun
1. Medium-sized tubular pasta in short pieces
What Scrabble words can I make with the letters in ziti?
3 Letter Words
2 Letter Words
Noun
1. Medium-sized tubular pasta in short pieces
3 Letter Words
2 Letter Words