dubious

doubtful, dubious

1. The constructions that follow doubtful correspond to the pattern outlined for doubt above, with whether and if still dominant but a that-clause now increasingly common:

• It is doubtful that in the right-to-life controversy the rights of the unborn child will be inviolate —A. E. Wilkerson, 1973

• It is doubtful whether the Peloponnesian detachment was dispatched during the actual celebration of the Olympic games —Classical Quarterly, 1976

• Murray was doubtful as to whether this would be enough —N. Tranter, 1987

• Even if Amelia McLean had made more ambitious claims, it is doubtful whether anyone would have listened to her —S. Reynolds, 1989

• It was doubtful if Midge would ever again sleep in their old bedroom —D. Rutherford, 1990

• It seems doubtful that such an item would have been produced much after c.1550 —J. Litten, 1991.

2. Doubtful and dubious overlap in meaning but they should not be confused. Doubtful implies uncertainty about facts, whereas dubious implies suspicion about value or genuineness. Both words can be used of people or situations, but dubious is not normally followed by any of the constructions described above in relation to doubt and doubtful. The following examples (in addition to those already given) will clarify the differences between doubtful and dubious: (doubtful)

• We're always a little doubtful about statements that have to be forced out of witnesses by revealing the extent of our prior information —R. Hill, 1987

• ‘Are you sure?’ she said doubtfully —T. Pratchett, 1990

• If your tap water is of doubtful quality then you must be prepared to remedy the situation or use rain water instead —Practical Fishkeeping, 1992

• Then meeting Sophie's anxious gaze, she said briskly, ‘Now don't look so doubtful.’ —M. Bowring, 1993

• (dubious) We still had the dubious privilege of representing two ‘resting’ actors —M. Babson, 1971

• Dreaming of luxury, of the quick buck dubiously acquired —R. Barnard, 1980

• Christine was a little dubious about Judith using brown eyeshadow, worrying that her eyes might end up looking bloodshot —She, 1989

• The right of people to know the human cost was overruled on the dubious grounds that this information could help the enemy —Action, 1991

• Voters are already dubious about the point of a deputy prime minister —Times, 2007.