The phrase "patterned upon" is usually used to refer to something that imitates or takes inspiration from another thing. Antonyms for this phrase could include original, innovative, unique, unconventional, and nonconformist. These words suggest that something is not derived from something else but rather, created independently. Additionally, antonyms for "patterned upon" could also include unstructured, disorganized, unmethodical, haphazard, erratic, and chaotic, which implies that there is no particular pattern or structure being followed. These antonyms provide a contrast to the idea of something being modeled after or copied from something else, highlighting the importance of individuality and creativity in various aspects of life.