Simple past tense and past participle of mildew.(verb)
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Use "mildewed" in a sentence
"The lake created its own kind of mildewed background to the wrought iron of the balconies and the screeching of the ravens that landed like wet face-flannels on the grass."
"He passes to consider the defect which has "mildewed" all the poetry written since Shelley, "the predominance of art over inspiration, of body over soul.""
""As an imitation poet," says Jonadab, "he was a kind of mildewed article, but as a play actor -- well, there may be some that can beat him, but _I_ never see 'em!""