A mixture of both "great" and "good" used by the Cheerleader in Teen Girl Squad (issue/tissue#4). Seemingly originated from a spelling mistake by Strong Bad.
"Grood! I mean... good. And great. Great and good."
comes from the word grood it is used as a RESPONSE when the word grood has been said; it can also be used as a substitute for grood when you are speaking to a large amount of people.
1.) Person 1 - "How are you?"
Person 2 - "I am grood!"
Person 1 - "Grooda!"
2.)"Hello and welcome! We will all have a grooda time today if everyone listens..."