unit of magnetic-field strength, in the centimetre-gram-second system of physical units. Named for the 19th-century Danish physicist Hans Christian Ørsted (Ørsted, Hans Christian), it is defined as the intensity of a magnetic field in a vacuum in which a unit magnetic pole (one that repels a similar pole at a distance of one centimetre with a force of one dyne) experiences a mechanical force of one dyne in the direction of the field. Before 1932 the oersted was known as the gauss, a name sometimes still applied, though now more properly used for the unit of magnetic induction.