# magnitude

Pronunciation: US say "MAG-ni-tood" /ˈmæɡnɪtud/; UK say "MAG-ni-tyood" /ˈmæɡnɪtjuːd/

## Noun

1. The size, extent, or importance of something, considered on its own or in comparison with other things.
   - Simple: How big or important something is, on its own or compared with other things.
   - _Engineers struggled to grasp the full magnitude of the damage to the bridge._
   - _The magnitude of the financial loss forced the company to close several offices._
2. A factor of roughly ten in size or quantity, used to express how much larger or smaller one thing is than another.
   - Simple: A factor of about ten in size, used to show how much bigger one thing is than another.
   - _The two populations differ by three magnitudes, a thousandfold gap._
   - _Storage capacity grew by a magnitude within just a few years._
3. A number expressing the energy released by an earthquake, such as on the Richter scale, with higher values indicating stronger quakes.
   - Simple: A number that shows how much energy an earthquake released, where bigger numbers mean stronger quakes.
   - _The quake's magnitude was revised upward after analysts reviewed the seismic data._
   - _A magnitude above eight can trigger destructive tsunamis along nearby coasts._
4. A measure of how bright a star appears from Earth, with lower values indicating brighter objects.
   - Simple: A number that tells how bright a star looks from Earth, where smaller numbers mean brighter stars.
   - _Sirius has a magnitude of about minus one, making it the brightest star in the night sky._
   - _Faint galaxies have a magnitude too high for the naked eye to detect._
5. A number assigned to something so that it can be compared numerically with others.
   - Simple: A number given to something so it can be compared with other numbers.
   - _The algorithm ranks data points by magnitude before grouping them._
   - _Two readings with the same magnitude are treated as equal in the model._
6. The norm of a vector, most often the Euclidean two-norm, representing the vector's overall length.
   - Simple: The length of a vector, found from how far it reaches in each direction.
   - _The magnitude of a vector equals the square root of the sum of its squared components._
   - _In physics, speed is simply the magnitude of the velocity vector._
7. A logarithmic measure expressing a ratio of intensities, used in astronomy to compare brightness on a fixed scale.
   - Simple: A brightness measure on a scale where each step means a fixed change in the amount of light.
   - _A difference of five magnitudes corresponds to a hundredfold change in brightness._
   - _The catalog lists a magnitude for every object it records._

## Origin

From Latin magnitūdō ("greatness, size"), formed from magnus ("great") and the suffix -tūdō.

Source: DictionaryAI, https://dictionaryai.com/define/magnitude (written from Wiktionary data, CC BY-SA 4.0: https://creativecommons.org/licenses/by-sa/4.0/).