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super-duper

American  
[soo-per-doo-per] / ˈsu pərˈdu pər /

adjective

Informal.

  1. extremely good, powerful, large, etc.; very super; marvelous or colossal.

super-duper British  
/ ˈsuːpəˈduːpə /

adjective

  1. informal extremely pleasing, impressive, etc: often used as an exclamation

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of super-duper

First recorded in 1935–40; rhyming compound with invented second element

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.