Richter scale

American  

noun

1. a scale, ranging from 1 to 10, for indicating the intensity of an earthquake.

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Richter scale British  

/ ˈrɪxtə /

noun

1. a scale for expressing the magnitude of an earthquake in terms of the logarithm of the amplitude of the ground wave; values range from 0 to over 9 Compare Mercalli scale See also magnitude

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Richter scale Scientific  

/ rĭk′tər /

1. A logarithmic scale used to rate the strength or total energy of earthquakes. The scale has no upper limit but usually ranges from 1 to 9. Because it is logarithmic, an earthquake rated as 5 is ten times as powerful as one rated as 4. An earthquake with a magnitude of 1 is detectable only by seismographs; one with a magnitude of 7 is a major earthquake. The Richter scale is named after the American seismologist Charles Francis Richter (1900–1985).

2. See Note at earthquake

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Richter scale Cultural  

1. A scale used to rate the intensity of earthquakes. The scale is open-ended, with each succeeding level representing ten times as much energy as the last. A serious earthquake might rate six to eight, and very destructive quakes rate higher.

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Discover More

No quake greater than nine has ever been recorded.

Etymology

Origin of Richter scale

1935–40; after Charles F. Richter (1900–85), U.S. seismologist

Compare meaning

How does richter-scale compare to similar and commonly confused words? Explore the most common comparisons:

• Mercalli scale vs. Richter scale

Example Sentences

Typically, one earthquake per year reaches a magnitude of 8.0 or higher, while around 15 others fall within the magnitude 7 range on the Richter scale, which measures the amount of energy released.

From Science Daily • Jan. 6, 2026

It registered 9.0 on the Richter scale, which measures the magnitude of the earthquake.

From Los Angeles Times • Jul. 8, 2025

Ms Starrs said the issue is now "off the Richter scale in terms of the extent of this phenomenon in every school".

From BBC • Jun. 5, 2025

Sunday's quake was preceded by three smaller ones of more than 4.0 magnitude, while the three on Monday morning were also more than 4.0 on the Richter scale.

From BBC • Feb. 10, 2025

Like Iris Chacon inside a washing machine during an earthquake, Richter scale 8.9.

From "Bodega Dreams" by Ernesto Quinonez