In a way that confuses, bewilders, or complicates matters; so as to create confusion or complexity.
From confounding + -ly adverbial suffix. A modern English adverb following standard formation from the present participle.
Physics is 'confoundingly' complex at quantum scales—electrons behave in ways that seem to violate logic (existing in two places at once), which is why even Einstein said 'if quantum mechanics hasn't profoundly shocked you, you haven't understood it.'
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