The phrase "day of doom" is often used to describe a time of impending destruction or disaster. Synonyms for this phrase could include terms such as "apocalypse," "judgment day," "end times," "cataclysm," or "armageddon." These words carry a weight of finality and impending destruction, often associated with religious or mythological beliefs about the end of the world. Other synonyms might include more specific phrases such as "death knell," "final reckoning," or "day of reckoning," all of which have connotations of a final and irreversible ending to something significant. While the phrase "day of doom" may evoke a sense of terror and uncertainty, the synonyms for this term convey a similar sense of foreboding and finality.