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1664, in the meaning defined above
Middle English erugo “mildew, plant rust,” borrowed from Medieval Latin, going back to Latin aerūgō “verdigris,” from aer-, aes “bronze, brass, copper” + -ūgō, suffix marking a surface layer or discoloration
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“Aerugo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/aerugo. Accessed 19 Jan. 2022.
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