super-duper

adjective
su·​per-du·​per | \ ˈsü-pər-ˈdü-pər How to pronounce super-duper (audio) \

Definition of super-duper

: of the greatest excellence, size, effectiveness, or impressiveness

First Known Use of super-duper

1938, in the meaning defined above

History and Etymology for super-duper

reduplication of super entry 1

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