To treat an area with fumes or smoke to disinfect it or kill pests and insects.
From Latin 'fumigatus' (past participle of fumigare, to smoke, from fumus + agere 'to do'), a medical term that became common in public health and agriculture.
Fumigation became famous in the 19th-20th centuries for fighting disease—the practice of filling ships and buildings with toxic gases to kill disease carriers and pests shaped modern public health, making 'fumigate' a term everyone knew.
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