Synonyms of the word

dubitable

• adj. Capable of being doubted; susceptible of being questioned.

doubtful

• adj. Subject to, or causing doubt.
• adj. Experiencing or showing doubt, sceptical.
• adj. Undecided or of uncertain outcome.
• adj. (obsolete) Fearsome, dreadful.
• adj. Improbable or unlikely.
• adj. Suspicious, or of dubious character.
• adj. Unclear or unreliable.
• n. A doubtful person or thing.

dubious

• adj. Arousing doubt; questionable; open to suspicion.
• adj. In disbelief; wavering, uncertain, or hesitating in opinion; inclined to doubt; undecided.

questionable

• adj. (obsolete) Inviting questions; inviting inquiry.
• adj. Problematic; open to doubt or challenge.
• adj. Of dubious respectability or morality.