Yes, cave is a Scrabble word!
...and is worth 9 points in Scrabble, and 11 points in Words with Friends
cave
Verb
1. Hollow out as if making a cave or opening
2. Explore natural caves
Noun
1. A geological formation consisting of an underground enclosure with access from the surface of the ground or from the sea
What Scrabble words can I make with the letters in cave?
3 Letter Words
2 Letter Words