Ma'anar ƙamus na kalmar "reactance" shine ma'auni na adawa da kwararar alternating current (AC) a cikin wutar lantarki saboda inductance ko capacitance. Yana da hadaddun yawa wanda ke wakiltar tasirin haɗin gwiwar duka inductive reactance (XL) da capacitive reactance (XC) a cikin da'irar AC. Ana auna amsawa yawanci a cikin ohms (Ω) kuma ana nuna shi da alamar "X". A cikin sauƙi, amsawa yana nufin juriya da inductor da capacitors ke bayarwa ga kwararar AC, yana haifar da bambancin lokaci tsakanin ƙarfin lantarki da na yanzu a cikin da'irar AC. Yana da mahimmancin ra'ayi a injiniyan lantarki kuma ana amfani dashi a cikin bincike da ƙira na da'irori na AC.