Yes, cash is a Scrabble word!
...and is worth 9 points in Scrabble, and 9 points in Words with Friends
cash
Verb
1. Exchange for cash
Noun
1. Money in the form of bills or coins
2. Prompt payment for goods or services in currency or by check
3. United States country music singer and songwriter (1932-2003)
What Scrabble words can I make with the letters in cash?
3 Letter Words
2 Letter Words