The Open Dictionary

doubtfully

adverb

UK/ˈdaʊt.fᵊl.i/
US/ˈdaʊt.fᵊl.i/

Definitions of doubtfully adverb

  1. in a manner that indicates a lack of certainty or belief

    • She looked at the suspicious package doubtfully, hesitant to open it.

    • "Are you sure this is correct?" he asked doubtfully.

    • He listened to the story doubtfully, unsure whether he should believe it.