Magnitude

[mag-ni-tood, -tyood] /ˈmæg nɪˌtud, -ˌtyud/

noun
1.
size; extent; dimensions:
to determine the magnitude of an angle.
2.
great importance or consequence:
affairs of magnitude.
3.
greatness of size or amount.
4.
moral greatness:
magnitude of mind.
5.
Astronomy.

6.
Mathematics. a number characteristic of a quantity and forming a basis for comparison with similar quantities, as length.
Idioms
7.
of the first magnitude, of utmost or major importance:
an artist of the first magnitude.
/ˈmæɡnɪˌtjuːd/
noun
1.
relative importance or significance: a problem of the first magnitude
2.
relative size or extent: the magnitude of the explosion
3.
(maths) a number assigned to a quantity, such as weight, and used as a basis of comparison for the measurement of similar quantities
4.
(astronomy) Also called apparent magnitude. the apparent brightness of a celestial body expressed on a numerical scale on which bright stars have a low value. Values are measured by eye (visual magnitude) or more accurately by photometric or photographic methods, and range from –26.7 (the sun), through 1.5 (Sirius), down to about +30. Each integral value represents a brightness 2.512 times greater than the next highest integral value See also absolute magnitude, visual magnitude
5.
(geology) Also called earthquake magnitude. a measure of the size of an earthquake based on the quantity of energy released: specified on the Richter scale See Richter scale
n.

c.1400, “greatness of size or character,” from Latin magnitudo “greatness, bulk, size,” from magnus “great” (see magnate) + -tudo, suffix forming abstract nouns from adjectives and participles (see -tude). Meaning “size, extent” is from early 15c. Of stars, “brightness,” from 1640s.
magnitude
(māg’nĭ-td’)