In a way that suggests doubt or mistrust; acting in a manner that raises questions or seems questionable.
From Latin 'suspiciosus' (distrustful), derived from 'suspicere' (to look up at, to suspect). The meaning stayed consistent: expressing doubt or distrust.
The word comes from the idea of 'looking up at someone suspiciously'—in Roman times, inferiors would look up to superiors with cautious doubt, creating the link between upward glances and suspicion.
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