english
1
general::
adj. unlikely: It is a doubtful if we need it. adj. skeptical: I am doubtful about her ability.
Simple Definitions
2
general::
adj. feeling doubt VERBS be, feel, look, seem, sound Eric was far from sure and Marion looked doubtful. | become | remain ADV. extremely, very | a bit, a little, rather PREP. about She was rather doubtful about the wisdom of eating the two-day-old food. unlikely VERBS be, look, seem | remain ADV. extremely, highly, very Even if we could go, which is highly doubtful, John wouldn't be able to come with us. | increasingly | a bit, a little, rather, somewhat
Oxford Collocations Dictionary