In a manner showing doubt, suspicion, or lack of confidence in someone or something.
From distrustful (adjective: showing distrust) plus -ly adverb suffix. Built from distrust (dis- 'not' + trust) with -ful forming the adjective.
When someone looks at you 'distrustfully,' their face is literally a warning sign—research shows that our ability to read suspicion in others evolved as a survival mechanism to detect potential threats.
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