I'm shocked at the 'suggestion' that he deliberately cheated. = The very 'suggestion' that he deliberately cheated is shocking (to me).
They were careful to avoid any 'suggestion' of impropriety. [=avoid doing anything that could be seen as improper]
There was some 'suggestion' of swelling around his ankle. [=his ankle appeared to be slightly swollen]
(..) it would have been only too easy. Perhaps it would be prudent to first teach the students. . . . . .to block unfriendly spells, professor. An excellent suggestion, Professor Snape. Let's have a volunteer pair. Potter, Weasley, how about you? Weasley's wand causes devastation (..)2002 Harry Potter and the Chamber of Secrets