doubtful

/ˈdaʊtfəl/
adjective
  1. Feeling uncertain or not sure about something.
    • She gave a doubtful look when he said he would be early.
    • I am doubtful that we will finish the project on time.
    • The teacher was doubtful about the student's excuse.
  2. Unlikely to happen or be true; not probable.
    • His chances of winning are doubtful.
    • It is doubtful that it will rain today.
    • The success of the plan is doubtful.
  3. Of questionable quality, honesty, or value.
    • The food at that restaurant is of doubtful quality.
    • He made a doubtful claim about his experience.
    • The company has a doubtful reputation.
Antonyms
What does "doubtful" mean? | whatsthatwordmean | whatsthatwordmean