A measure of the energy released by an earthquake (e.g. on the Richter scale).
A number, assigned to something, such that it may be compared to others numerically
An order of magnitude.
The absolute or relative size, extent or importance of something.
Of a vector, the norm, most commonly, the two-norm.
The apparent brightness of a star, with lower magnitudes being brighter; apparent magnitude
A ratio of intensity expressed as a logarithm.
Lack of importance.