The great magnitude of the Grand Canyon.

- An example of magnitude is the depth of the Grand Canyon.
- An example of magnitude is the size of the problem of world hunger.

Magnitude is defined as large in size or very important.

## magnitude

- greatness, specif.
- of size
- of extent
- of importance or influence
- Obs. of character

- size or measurable quantity: the
*magnitude*of a velocity - loudness (of sound)
- importance or influence

- size or measurable quantity: the
- Astron. a number representing the apparent brightness of a celestial body: originally a number in a scale of values 1-6 and applied only to objects (excluding the sun and moon) visible to the naked eye, with the brightest stars at
*c.*1.5 (1 is the*first magnitude*) and stars at*c.*6 (*sixth magnitude*) being barely visible, the scale now includes the sun (at ?26.7) and moon (*c.*?12.7 when full) as well as the faintest objects visible telescopically (*c.*36): each increase of one magnitude represents an increase of 2.512 times the brightness - Geol. a measure of the amount of energy released by an earthquake
- Math. a number given to a quantity for purposes of comparison with other quantities of the same class

Origin of magnitude

Classical Latin*magnitudo*from

*magnus,*great: see magni-

**magnitude Idioms**

of the first magnitude

of the greatest importance

## magnitude

noun

**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.*-
*Astronomy***a.**The brightness of a celestial body on a numerical scale for which brighter objects have smaller values. Differences in magnitude are based on a logarithmic scale that matches the response of the human eye to differences in brightness so that a decrease of one magnitude represents an increase in apparent brightness by a factor of 2.512. Also called*apparent magnitude*.**b.**A unit on such a scale of brightness. -
*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. -
*Geology*A measure of the amount of energy released by an earthquake, as indicated on the Richter scale.

Origin of magnitude

Middle English*from*Old French

*size*

*from*Latin

*magnitūdō*

*greatness, size*

*from*

*magnus*

*great*; see

*meg-*in Indo-European roots.

## magnitude

Noun

(*countable and uncountable*, *plural* magnitudes)

- (uncountable, countable) The absolute or relative size, extent or importance of something.
- (countable) An order of magnitude.
- (mathematics) A number, assigned to something, such that it may be compared to others numerically
- (mathematics) Of a vector, the norm, most commonly, the two-norm.
- (astronomy) The apparent brightness of a star (on a negative, logarithmic scale); apparent magnitude
- (seismology) A measure of the energy released by an earthquake (e.g. on the Richter scale).

Origin

From Latin *magnitÅ«dÅ* (“greatness, size"); *magni-* +"Ž *-itude*