Superlative form of wicked: most wicked.(adjective)
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Use "wickedest" in a sentence
"San Francisco was often called the wickedest city in America."
"He read of Aleister Crowley, dubbed the wickedest man in the world, of his beliefs and essays, and, in particular, his search in the early twentieth century for the forgotten places of magic and religion."
"The film has Simon Callow playing Aleister Crowley, once dubbed the wickedest man in the world."