Superlative form of shrill: most shrill.(adjective)
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Use "shrillest" in a sentence
"By contrast, Franklin Graham became one of the shrillest of the Far Right Republican Party boosters and also a harsh anti-Islamic activist who capitalized on the post-9/11 political climate of fear that burgeoned, in many instances, into paranoia about the Muslim "Other.""
"Sara saw him coming and screamed her shrillest and savagest at him."
"Obama and our political elite need to learn from China to start representing the needs of the majority, not of the shrillest commentators on Fox News or the deep pocketed few."