Definition of WONDERFUL in the Definitions.net dictionary. Meaning of WONDERFUL. What does WONDERFUL mean? Information and translations of WONDERFUL in the most comprehensive dictionary definitions resource on the web. The meaning of WONDERFUL is exciting wonder : marvelous, astonishing. How to use wonderful in a sentence. Wonderful is better than good — it's even better than great, like your wonderful luck — finding buried treasure on your very first diving expedition. Wonderful definition: excellent; great; marvelous.. See examples of WONDERFUL used in a sentence.