A person who douses; someone who extinguishes a fire or sprinkles liquid on something.
From douse plus the agent noun suffix -er, indicating one who performs the action of dousing. Douse comes from perhaps Dutch douse or an onomatopoetic origin.
Medieval firefighting was all about 'dousers'—teams of people with buckets who'd race to splash water on burning buildings, making them some of history's first organized emergency responders!
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