The act of exterminating; total destruction; eradication; excision; as, the extermination of inhabitants or tribes, of error or vice, or of weeds from a field.(noun)
Elimination.(noun)
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Use "extermination" in a sentence
"Anyone preaching extermination is ignorant of how ecosystems work."
"To throw a whole ecosystem out of whack for our pleasure, especially by way of extermination is foolish."
"Despite its rather idyllic sounding name (birch tree meadow), Birkenau housed gas chambers and four crematoria and therefore served as the main extermination unit of Auschwitz."