In a way that presents a challenge or invites confrontation; with a tone suggesting defiance or provocation.
From challenging (present participle of challenge) plus the adverb suffix -ly (from Old English 'lice' meaning like or body). The -ly suffix converts adjectives and participles into adverbs.
The suffix -ly magically transforms adjectives into adverbs that tell us HOW something happens—'challenging' describes what something IS, while 'challengingly' describes HOW someone DOES something.
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