Possible Definitions:
1. Resistance (n.) The act of resisting; opposition, passive or active.
2. Resistance (n.) The quality of not yielding to force or external pressure; that power of a body which acts in opposition to the impulse or pressure of another, or which prevents the effect of another power; as, the resistance of the air to a body passing through it; the resistance of a target to projectiles.
3. Resistance (n.) A means or method of resisting; that which resists.
4. Resistance (n.) A certain hindrance or opposition to the passage of an electrical current or discharge offered by conducting bodies. It bears an inverse relation to the conductivity, -- good conductors having a small resistance, while poor conductors or insulators have a very high resistance. The unit of resistance is the ohm.
