1. adjective, childish slang Excellent; awesome; fantastic. Usually hyphenated and used before a noun. Tommy got a super-duper new video game console for Christmas. Jessica is super-duper popular. There's no way she'd go to the school dance with me. Aw, jeez, I'm super-duper sorry about that!
2. adverb, childish slang Extremely; very much; to a great degree. We're all super duper excited to meet your new girlfriend! It was super duper hot in Spain, so we stayed on the beach most of the time.
mod. excellent. That’s just super-duper. Couldn’t have asked for better.