It is what some crazy girl would say when she thought something was fantastic. She snacked so much that the wordsnack got stuck in her vocabulary permanently, and everyone thought it sounded bitchin'. So now it is an official word that means fantastic while snacking.
Looks delicious even though not edible.
That man has the most snacktastic abs I have ever seen.
This is a female who is a skank, but you still want to hit that. She is defined as a skank who is kind of fly (fantastic).
Yo dog, let's leave this club. They ain't no ho's up here that I want to hit. Oh wait, that one over on the pole is skanktastic and so is the other one dancing in the cage! My bad.