Yes, tusk is a Scrabble word!
...and is worth 8 points in Scrabble, and 9 points in Words with Friends
tusk
Verb
1. Stab or pierce with a horn or tusk
2. Remove the tusks of animals
Noun
1. A hard smooth ivory colored dentine that makes up most of the tusks of elephants and walruses
2. A long pointed tooth specialized for fighting or digging; especially in an elephant or walrus or hog
What Scrabble words can I make with the letters in tusk?
3 Letter Words
2 Letter Words