A unit of magnetic field strength equal to 10-9 tesla or 10-5 gauss. The unit is used in geology to measure small changes in the Earth's magnetic field
Russ Rowlett (Director), How Many? A Dictionary of Units of Measurement, Center for Mathematics and Science Education University of North Carolina, USA 2005. http://www.unc.edu/~rowlett/units/dictA.html, (Unit of Meas and Covr Factors - Amer) {608}