Question

give meaning of term short circuiting and overloading in an electric circuit

Answer 1

Short circuit - touching of the live and neutral wire due to faulty insulation.
Overloading - connection of more than one device \ appliance to a single socket.

Answer 2

short circuit : short circuit occurs when naked live and neutral wires touch each other. in such case,the resistance of the circuit becomes very less. now according to Ohms law, current inversely proportional to resistance of the circuit raises the current to a significant amount. As a result, the wires become hot and a spark in caused by joules heating effect of current.This situation is known as short circuiting.
overloading: A large amount of current is with drawn from the circuit, when a large number of electrical appliances of high power-rating are switched on at the same time or connected in a single multi plug .This situation is called over loading