The worst name u could ever be called. It means ur fat and stupid. It was created when spongebob called Patrick tubby while they were playing and made him cry.
A perfect princess who shares their snacks with all their friends and who always is up for a good time.
Girl 1: "Becky is such a Becky."
Girl 2: "Yeah you're right, but Becky's little sister is such a Tubby."
Girl 1: "You're right! Let's invite her instead. Maybe she'll bring cookies again."