Cornfed is an adjective that refers to an individual or animal that is raised on corn or has eaten a diet mainly consisting of corn. Opposite to this word, there are several antonyms that can be used to convey a different meaning. For instance, grass-fed is a word that refers to an individual or animal that is raised on a diet of grass, not corn. Similarly, grain-free, vegan, and organic could also be considered as antonyms for cornfed. These words all imply a different lifestyle or dietary choice, significantly contrasted with the concept of cornfed. Therefore, the use of antonyms helps to broaden our language and convey a more diverse set of meanings.