Simple past tense and past participle of deaden.(verb)
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Use "deadened" in a sentence
"Many of the leading organ builders now employ this thicker construction, and it is no uncommon thing to find Swell boxes measuring three inches in thickness and "deadened" with sawdust or shavings between the layers of wood of which they are formed."
"A log cabin, and, occasionally, a stable and corn-crib, and a field of a dozen acres, the timber girdled or "deadened," and fenced, are enough for his occupancy."
"Big trees were "deadened," or killed, by cutting a"