n. [ So called from the German electrician, G. S. Ohm. ] (Elec.) The standard unit in the measure of electrical resistance, being the resistance of a circuit in which a potential difference of one volt produces a current of one ampére. As defined by the International Electrical Congress in 1893, and by United States Statute, it is a resistance substantially equal to 109 units of resistance of the C. G. S. system of electro-magnetic units, and is represented by the resistance offered to an unvarying electric current by a column of mercury at the temperature of melting ice 14.4521 grams in mass, of a constant cross-sectional area, and of the length of 106.3 centimeters. As thus defined it is called the international ohm. [ 1913 Webster ]

Ohm's law (Elec.), the statement of the fact that the strength or intensity of an electrical current is directly proportional to the electro-motive force, and inversely proportional to the resistance of the circuit. [ 1913 Webster ]

n. [ Ohm + meter. ] (Elec.) An instrument for indicating directly the electrical resistance of a circuit in ohms. [ Webster 1913 Suppl. ]