Simple past tense and past participle of winnow.(verb)
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Use "winnowed" in a sentence
"But it was not until the last few weeks that McCain winnowed his list to five or six finalists."
"They try them, as silver in the furnace is refined from its dross; they purge them, as wheat in the barn is winnowed from the chaff; and they make them white, as cloth by the fuller is cleared from its spots."
"At what point do we see this really huge field kind of winnowed down to a handful of serious contenders, do you think?"