- Yup is defined as slang for yes.
An example of yup used as an interjection is in the sentence, "Yup, I'll go to the supermarket today."
Yup means yes.
yup definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
Slang yes: an affirmative reply
yup definition by American Heritage Dictionary
Origin: Alteration of yep.