adjective

1. (of a statement) Arousing doubt; questionable; open to suspicion.

   “After he made some dubious claims about the company, fewer people trusted him.”

2. (of a person) In disbelief; wavering, uncertain, or hesitating in opinion; inclined to doubt; undecided.

   “She was dubious about my plan at first, but later I managed to persuade her to cooperate.”