Yes, gage is a Scrabble word!
...and is worth 6 points in Scrabble, and 8 points in Words with Friends
gage
Verb
1. Place a bet on
Noun
1. Street names for marijuana
2. A measuring instrument for measuring and indicating a quantity such as the thickness of wire or the amount of rain etc.
What Scrabble words can I make with the letters in gage?
3 Letter Words
2 Letter Words