The phrase "most uncompounded" suggests a state of simplicity or lack of complexity. Antonyms for this phrase could include more complex, intricate, or convoluted. Other antonyms might include multifaceted, nuanced, or layered. These words suggest that something is not simple or straightforward, but instead has many different aspects or levels of meaning. In contrast to "most uncompounded," these antonyms might describe something that requires more effort to understand or navigate. Nonetheless, they can also signify greater depth or richness, and may be used to describe anything from a work of literature to a simple conversation.