uni·​for·​mi·​tar·​i·​an·​ism ˌyü-nə-ˌfȯr-mə-ˈter-ē-ə-ˌni-zəm How to pronounce uniformitarianism (audio)
: a geologic doctrine that processes acting in the same manner as at present and over long spans of time are sufficient to account for all current geological features and all past geological changes compare catastrophism

Example Sentences

Recent Examples on the Web This is reassuring, because too often historical scientists fixate on uniformitarianism to an almost irrational extent. Razib Khan, Discover Magazine, 23 June 2013 Each of these works critiqued uniformitarianism’s assumption of slow, gradual, evolutionary change, contrasted with neo-catastrophism, wars and revolutions being the social equivalents. Thomas Reifer, San Diego Union-Tribune, 20 Nov. 2022 Ever since geology came into its own as a science in the 19th century, much of the field has been influenced by the concept of uniformitarianism—that the present is the key to the past. Riley Black, Smithsonian Magazine, 19 Apr. 2022 Substantive uniformitarianism, and incorrect theory, should be abandoned. Brian Romans, WIRED, 8 Jan. 2011

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'uniformitarianism.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1865, in the meaning defined above

Time Traveler
The first known use of uniformitarianism was in 1865

Dictionary Entries Near uniformitarianism

Cite this Entry

“Uniformitarianism.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/uniformitarianism. Accessed 6 Jun. 2023.

Kids Definition


uni·​for·​mi·​tar·​i·​an·​ism ˌyü-nə-ˌfȯr-mə-ˈter-ē-ə-ˌniz-əm How to pronounce uniformitarianism (audio)
: a principle in geology that states that processes going on in nature at the present time can explain geological changes in the past

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