Definitions
1.VerbTo be undecided about; to lack confidence in; to disbelieve, to question."He doubted that was really what you meant.; I had no wish to go, though I doubt if they would have noticed me even if I had."
2.VerbTo harbour suspicion about; suspect.
3.VerbTo anticipate with dread or fear; to apprehend.
4.VerbTo fill with fear; to affright.
5.VerbTo dread, to fear.
6.NounDisbelief or uncertainty (about something); a particular instance of such disbelief or uncertainty."There was some doubt as to who the child's real father was.; I have doubts about how to convert this code to JavaScript."
7.NounA point of uncertainty, especially a yes/no or a multiple-choice question"Ma'am, I have a doubt about today's lecture"
8.Nouna question (that one has)