Yes, hypo is a Scrabble word!
...and is worth 12 points in Scrabble, and 11 points in Words with Friends
hypo
Noun
1. A compound used as a fixing agent in photographic developing
2. A piston syringe that is fitted with a hypodermic needle for giving injections
What Scrabble words can I make with the letters in hypo?
3 Letter Words
2 Letter Words