Pee-wee is a term used to describe something small, insignificant or inferior. Antonyms for this word are therefore words that describe something large, significant, or superior. Such antonyms include big, enormous, giant, vast, immense, huge, mammoth, sturdy, tough, substantial, powerful, gigantic, and monstrous. Opposite terms of pee-wee are usually more descriptive, fitting, and appropriate in specific contexts. For instance, giant would be an appropriate antonym for pee-wee in a fantasy story where size matters, while substantial and sturdy would work well in a construction or engineering context.