To destroy the composure of; to disturb or agitate.
To disarrange, or throw into a state of disorder.
To attack unexpectedly.
To take unawares.
To do something to (a person) that they are not expecting, as a surprise.
To cause (someone) to feel unusually alarmed or delighted by something unexpected.
To undergo or witness something unexpected.
To cause surprise.
The feeling that something unexpected has happened.
Something unexpected.