In a manner characteristic of Dadaism; in an absurd, irrational, or deliberately nonsensical way.
From 'Dadaistic' plus the adverb-forming suffix '-ly', creating an adverb that describes how something is done in a Dadaist manner.
If someone performs or acts 'dadaistically,' they're deliberately embracing chaos and meaning-lessness—it's a rare word, but perfect for describing someone who rejects conventional logic in favor of absurdist humor or artistic expression.
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