In a way that disturbs or confuses; in a manner that throws someone off balance or surprises them.
From 'disconcerting' + -ly. Adverbial form describing how something is done in a way that causes disconcertment.
This adverb is perfect for describing horror movie moments—'the door creaked open disconcertingly slowly' makes you anticipate something terrible is about to happen because the speaker is unsettled by what they're witnessing.
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