doubtful
//ˈdaʊtfəl//
Adjective
doubtfulCanonical form
more doubtfulComparative
most doubtfulSuperlative
1
Feeling uncertain or unsure about something; not convinced.
I'm doubtful about whether we can finish the project on time.
2
Not likely to happen, succeed, or be true; questionable.
It is doubtful whether the project will be completed on time.
3
Of uncertain quality or reliability; not to be trusted.
The information from that website is doubtful.