Directly derived from an actual interview with the creator himself, Masashi kishimoto.
- Is Naruto's favorite phrase, "dattebayo" modeled on anything?
K: That isn't really modeled on anything either. When I thought of childlike
speech, "dattebayo" instantly came to mind. It's like it's become a part of
Naruto, and even now it brings out his "mischievousness".
I guess it's just up to fans to determine for themselves what it truly means...
Maybe there's no real definition to it, dattebayo!