geology

American  

[jee-ol-uh-jee] / dʒiˈɒl ə dʒi /

noun

plural

geologies

1. the science that deals with the dynamics and physical history of the earth, the rocks of which it is composed, and the physical, chemical, and biological changes that the earth has undergone or is undergoing.

2. the study of this science.

3. the geologic features and processes occurring in a given region on the earth or on a celestial body.

   the geology of Mars; the geology of eastern Kentucky.

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geology British  

/ dʒɪˈɒlədʒɪ, ˌdʒɪəˈlɒdʒɪkəl /

noun

1. the scientific study of the origin, history, structure, and composition of the earth

2. the geological features of a district or country

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geology Scientific  

/ jē-ŏl′ə-jē /

1. The scientific study of the origin of the Earth along with its rocks, minerals, land forms, and life forms, and of the processes that have affected them over the course of the Earth's history.

2. The structure of a specific region of the Earth, including its rocks, soils, mountains, fossils, and other features.

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geology Cultural  

1. The science devoted to the study of the Earth, particularly the solid Earth and the rocks that compose it.

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Other Word Forms

• geological adjective
• geologically adverb
• geologist noun

Etymology

Origin of geology

First recorded in 1680–90; geo- + -logy

Explanation

Geology is the study of the Earth and what it's made of, including its natural history. Just as biology is the study of earth's life forms, geology is the study of the earth itself. Geology tells us where lakes once were, where volcanoes erupted, where glaciers pushed up mountains and then melted. Geologists — people who study geology — tell us where to find oil, coal and diamonds and then they explain how they got there. If you find the natural world beautiful and interesting, you might enjoy studying geology.

Example Sentences

They both have a background in geology and the oil and gas industry, and Marguerite now runs a wool business from home.

From BBC • Apr. 11, 2026

Commander Reid Wiseman said the crew had a lot of scientific work to do and it was "probably the most critical lunar observations for our geology team".

From BBC • Apr. 9, 2026

Noah Petro, head of NASA's planetary geology lab, told AFP that the Moon will look to the astronauts "about the size of a basketball held at arm's length."

From Barron's • Apr. 5, 2026

The work pushed her beyond biology into chemistry, physics and geology, she said.

From Science Daily • Apr. 3, 2026

“Kate’s right,” said Sticky, looking up from a geology book.

From "The Mysterious Benedict Society" by Trenton Lee Stewart

Related Words

• earth science
• geopolitics
• topography