niggling doubt/worry/suspicion etcWORRIEDa slight doubt etc that you cannot stop thinking about 使人心烦的疑虑/担心/怀疑等 SYN naggingniggling doubt/worry/suspicion etc• Always, in the background, in the dim recesses of her mind, there had been that niggling doubt.• Of course, this is usually so, but I am having little niggling doubts about such a sweeping statement.• Almost immediately, the fretting, niggling worries and the sense of fearful anticipation began to return.• And here a niggling doubt enters the mind.• There was, however, a niggling doubt in the minds of some of the jurors.• Nor did it remove the niggling suspicion that Isabel was hiding something.• There remains the niggling doubt that this delay has something to do with our muddled sentimentality towards animals.
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