Question

Define electric resistance of a conductor?

Answer 1

conductor means which passes electricity through it
resistance is dependent upon the source we use

Answer 2

When an electric current passes through any substance some of the electric current gets wasted due to electric resistance and as a result the substance heats up and starts to give out light.A material whose electric resistance is less compared to others is known as a conductor.
Even an electric conductor does not conducts electricity in a perfect manner
a conductor also offers some resistance when a current flows through it this is known as resistance of a conductor.
This phenomenon is used in electric geysers and also observed in an electric bulb.
Even there are some conductors which offer no resistance and current flows through some them just like an object on frictionless surface these are known as superconductors but they only occur below room temperature.
There are many detailed ways to calculate resistance offered by a wire one of them being ohms law v=i÷r.
You can learner about them in detail.

Hope I helped