Yes, dunk is a Scrabble word!
...and is worth 9 points in Scrabble, and 11 points in Words with Friends
dunk
Verb
1. Immerse briefly into a liquid so as to wet, coat, or saturate
2. Make a dunk shot, in basketball
3. Dip into a liquid while eating
Noun
1. A basketball shot in which the basketball is propelled downward into the basket
What Scrabble words can I make with the letters in dunk?
3 Letter Words
2 Letter Words