The term 'magnetic unit' refers to three different units of measurement used to measure magnetic fields. The first is the tesla (5 letters), which is a unit of measurement for the strength of a magnetic field. It is named after the physicist Nikola Tesla. The second is the gauss (5 letters), which is a unit of magnetic flux density. It is named after the mathematician and physicist Carl Friedrich Gauss. The third is the oersted (7 letters), which is a unit of magnetizing force. It is named after the Danish physicist Hans Christian Oersted.