In a way that deceives or is intended to mislead; in a manner that tricks or fools someone.
From the present participle deceiving plus the adverb suffix -ly. Deceive comes from Latin decipere (to catch, ensnare), so deceivingly means in an ensnaring manner.
The word 'deceivingly' can apply to appearances as well as actions—something can be deceivingly simple or deceivingly cheap, suggesting that first impressions lie about what's really true.
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