The word "auguration" is not typically found in most dictionaries, and thus it has no conventional antonyms. However, if we assume that "auguration" is intended to refer to "augury" - which means the practice of predicting the future based on omens or signs - then we can identify some potential antonyms. These might include "chance," "accident," "randomness," or "unpredictability." Alternatively, one might use antonyms in the sense of describing opposite qualities of augury itself - such as skepticism, rationalism, or scientific inquiry. Ultimately, the choice of antonym depends on the intended meaning and context of the word being used.