The term ELEC. UNIT is used to refer to the five electrical units of measure: AMP (3 letters), MHO (3 letters), OHM (3 letters), REL (3 letters), and FARAD (5 letters). An AMP is a unit of electric current, MHO is a unit of electrical conductance, OHM is a unit of electrical resistance, REL is a unit of electrical inductance, and FARAD is a unit of electrical capacitance. All of these units are used to measure different aspects of electricity.