What does SHOCK mean?

noun

1. the feeling of distress and disbelief that you have when something bad happens accidentally“his mother's death left him in a daze”
2. the violent interaction of individuals or groups entering into combat“the armies met in the shock of battle”
3. a reflex response to the passage of electric current through the body“subjects received a small electric shock when they made the wrong response”
4. (pathology) bodily collapse or near collapse caused by inadequate oxygen delivery to the cells; characterized by reduced cardiac output and rapid heartbeat and circulatory insufficiency and pallor“loss of blood is an important cause of shock”
5. an instance of agitation of the earth's crust“the first shock of the earthquake came shortly after noon while workers were at lunch”
6. an unpleasant or disappointing surprise“it came as a shock to learn that he was injured”
7. a pile of sheaves of grain set on end in a field to dry; stalks of Indian corn set up in a field“corn is bound in small sheaves and several sheaves are set up together in shocks”
8. a bushy thick mass (especially hair)“he had an unruly shock of black hair”