In a manner showing worry, anxiety, or nervous concern about something.
From apprehensive + -ly suffix. Apprehensive comes from apprehension + -ive (tending toward/having the quality of). The word evolved to emphasize the anxiety sense of apprehension over the understanding sense.
Dogs often look at their owners apprehensively when facing new situations—researchers now call this 'apprehensive checking' and it shows humans and dogs share the same anxiety-monitoring behavior!
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