noun The refusal to accept or comply with something. (they displayed a narrow-minded resistance to change) The ability not to be affected by something, especially adversely. (some of us have a lower resistance to cold than others) The impeding or stopping effect exerted by one material thing on another. (air resistance was reduced by streamlining) The degree to which a substance or device opposes the passage of an electric current, causing energy dissipation. By Ohm's law resistance (measured in ohms) is equal to the voltage divided by the current.