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total destruction; complete destruction; annihilation; being wiped out
total defeat; complete failure
激しい戦闘で部隊は全滅に近い被害を受けた。
The unit suffered near-total destruction in the fierce battle.
害虫を全滅させるために農薬を散布した。
Pesticides were sprayed to completely eradicate the pests.
期末試験で数学の問題が全滅だった。
I got all the math questions wrong on the final exam.