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Synonyms

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.
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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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.

geology Cultural  

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

Other Word Forms

  • geological adjective
  • geologically adverb
  • geologist noun

Etymology

Origin of geology

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

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

From Barron's • Apr. 5, 2026

But even with original documents, said François Kervyn de Meerendré, the Belgian museum’s head of geology, “it’s not a magic recipe where you find maps for lithium or gold. It gives you some indication.”

From The Wall Street Journal • Mar. 28, 2026

In Wales, Scotland and Northern Ireland groundwater flooding is often less extensive than in England due to the bedrock geology and topography.

From BBC • Feb. 18, 2026

The project involved experts in archaeology, geology, and ecology from The Netherlands, Denmark, France, and UK.

From Science Daily • Feb. 12, 2026

In geology class, the teacher, Mr. Dodge, was talking about the petrified wood forests near George, Washington, on the Columbia River, and how it was pretty amazing that wood could turn into rock.

From "The Absolutely True Diary of a Part-Time Indian" by Sherman Alexie

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.