The phrase "great mishap" refers to a significant or catastrophic event that has caused harm, damage, or disruption. There are several synonyms for this term, including disaster, calamity, tragedy, cataclysm, misfortune, and setback. These words convey the idea of a sudden and unexpected crisis or difficulty that has significant consequences. Other synonyms for "great mishap" might include accident, blunder, failure, or mistake, depending on the context in which the phrase is used. Regardless of the exact wording, the implication of any synonym for "great mishap" is that something has gone terribly wrong, with profound and lasting implications for those affected.