The most common and most likely answer to this crossword clue is the 8 letter word DOOMSDAY
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The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does DOOMSDAY mean?
DOOMSDAY noun- The day when God is expected to judge the world; end times.
- Judgement day; the day of the Final Judgment; any day of decisive judgement or final dissolution.
- Concerned with or predicting future universal destruction.
- Given to or marked by forebodings or predictions of impending calamity.
- Capable of causing widespread or total destruction.