This is the 996th most frequent Icelandic word.
grunur
Suspicion; doubt.
In this context, 'grun' is used to describe something that causes someone to feel doubt or suspicion.
Það vakti grun hjá honum að hurðin stóð opin.
It raised suspicion with him that the door was open.
The word 'grun' here is used to express suspicion or doubt about a situation.
Ég hef grun um að eitthvað sé ekki í lagi.
I have a suspicion that something is not right.
'Grun' here signifies a feeling or thought of suspicion directed towards an individual.