Yes, jag is a Scrabble word!
...and is worth 11 points in Scrabble, and 14 points in Words with Friends
jag
Verb
1. Cut teeth into; make a jagged cutting edge
Noun
1. A sharp projection on an edge or surface
2. A slit in a garment that exposes material of a different color underneath; used in Renaissance clothing
3. A flap along the edge of a garment; used in medieval clothing
4. A bout of drinking or drug taking
What Scrabble words can I make with the letters in jag?
2 Letter Words