noun (n)

• a material's opposition to the flow of electric current; measured in ohms(noun.phenomenon)

  Synonym:
  electric resistance, electrical resistance, ohmic resistance, resistance, resistivity
  

  source: wordnet30
• The apparent resistance in an electric circuit to the flow of an alternating current, analogous to the actual electrical resistance to a direct current, being the ratio of electromotive force to the current. It is equal to R² + X², where R = ohmic resistance, X = reactance. For an inductive circuit, X = 2πfL, where f = frequency and L = self-inductance; for a circuit with capacity X = 1 ÷ 2πfC, where C = capacity.(noun)

  source: webster1913