Learner's definition of SUSPICION
1 [noncount] : a feeling that someone is possibly guilty of a crime or of doing something wrong
Her strange behavior has aroused suspicion. [=has made people think that she is doing something wrong]
He is under suspicion of [=suspected of] selling illegal drugs.
He was arrested on suspicion of robbery. [=he was arrested because the police suspect that he committed a robbery]
They are not above/beyond suspicion. [=they are not considered to be obviously or certainly innocent and unable to be suspected]
2 [count] : a feeling that something bad is likely or true
There has long been a suspicion that the painting is a fake.
There was not the slightest suspicion of a trap. [=no one suspected a trap]
I thought the water might be making us sick, and my suspicions were confirmed by the lab tests.
The note aroused her suspicions that he was having an affair.
I have a sneaking suspicion that those cookies aren't really homemade.
3 : a feeling of doubt
4 [singular] : a very small amount of something