1 a [count] : a sudden usually unpleasant or upsetting feeling caused by something unexpected — usually singular ▪ If you haven't been there for a while, prepare yourself for a shock: the place has changed a lot. ▪ a terrible/nasty shock ▪ You're in for a big/rude shock if you think this job will be easy. — often + of ▪ the shock of discovering that someone you love has betrayed you ▪ He got the shock of his life [=he was very unpleasantly surprised] when he saw his own name on the list. — see also culture shock, sticker shock
b [count] : something unexpected that causes a sudden usually unpleasant or upsetting feeling — usually singular ▪ Seeing his parents at the rock concert was a shock. ▪ Her death came as a shock to the family. ▪ It came as quite a shock. ▪ It is something of a shock to learn/discover that she is guilty.
c [noncount] : a state in which you are experiencing a sudden usually unpleasant or upsetting feeling because of something unexpected
▪ She stood there in shock as he told her what had happened. ▪ They were in a state of shock after hearing the news. = They were in shock over the news.
d [count] : a sudden bad change in something
▪ Unfortunately, it's the poor who are most vulnerable to this kind of economic shock. ▪ oil/energy price shocks 2 [noncount] medical : a serious condition in which the body is not able to get enough blood to all the parts of the body ◊Shock is caused by a severe injury, a large loss of blood, etc.
▪ She was treated/hospitalized for shock after the accident. ▪ He was in (a state of) shock. = He was suffering from shock. — see also shell shock, toxic shock syndrome 3 [count] : the effect of a strong charge of electricity passing through the body of a person or animal — usually singular ▪ When the wires touched, I got a shock. ▪ an electric shock ▪ I walked across the carpet and then got a shock when I touched the metal doorknob. 4 [count] : shock absorber — usually plural ▪ The car needs new shocks. 5 : a violent shake [count] ▪ an earthquake shock ▪ The building is made to withstand large shocks. — often + of ▪ the shock of the explosion [noncount] ▪ The car's bumper absorbs shock on impact.