"Chance a million" refers to a situation with very low probability of success or likelihood of occurrence. There are several synonyms for this phrase including "long shot," "remote possibility," and "slim chance". Other similar phrases include "fat chance," "pipe dream," and "wishful thinking." These words and phrases denote a seemingly impossible scenario, where the chances of success are minimal or next to none. They are often used to express disbelief or skepticism towards a risky or improbable endeavor. In summary, "chance a million" and its synonyms depict an unlikely, almost impossible outcome, effectively conveying the severity of the odds.