magnitude

(măgˈnĭ-to͞odˌ, -tyo͞odˌ)

1. a. Greatness of rank or position: “such duties as were expected of a landowner of his magnitude” (Anthony Powell).
   b. Greatness in size or extent: The magnitude of the flood was impossible to comprehend.
   c. Greatness in significance or influence: was shocked by the magnitude of the crisis.
2. Astronomy The degree of brightness of a celestial body designated on a numerical scale, on which the brightest star has magnitude -1.4 and the faintest visible star has magnitude 6, with the scale rule such that a decrease of one unit represents an increase in apparent brightness by a factor of 2.512. Also called apparent magnitude.
3. Mathematics
   a. A number assigned to a quantity so that it may be compared with other quantities.
   b. A property that can be described by a real number, such as the volume of a sphere or the length of a vector.
4. Geology A measure of the amount of energy released by an earthquake, as indicated on the Richter Scale.