To dream of a hornet represents a person or situation that is a lingering threat, or problem that is lying beneath the surface. You may have a fear of reprisal from standing up for yourself, or concerns about a situation getting out of control.
To be stung by a hornet symbolizes anger, vengeance, and revenge.
A hornet’s nest would symbolize a very sensitive issue you want to steer clear of. You may be concerned about a possible confrontation.