A variable resistor consisting of a two-electrode resistor made of semiconductor material and having voltage-dependent nonlinear resistance that drops with an increase in applied voltage.

It can be used to protect sensitive equipment from power spikes or lightning strikes by shunting the energy to the ground.

1. A voltage-dependent variable resistor which is normally used to protect sensitive equipment from power spikes or lightning strikes by shunting the energy to the ground or a two-element semiconductor with nonlinear resistance in which the resistance drops as the applied voltage increases.
2. A blend of varied and resistor.

• Varied: That which changes periodically or in succession and differs or alternates.
• Resistor: An electrical component that limits or regulates the flow of electrical current in an electronic circuit and it can also be used to provide a specific voltage for an active device such as a transistor.