ag·​gra·​da·​tion | \ ˌa-grə-ˈdā-shən How to pronounce aggradation (audio) \

Definition of aggradation

: a modification of the earth's surface in the direction of uniformity of grade by deposition

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Other Words from aggradation

aggradational \ ˌa-​grə-​ˈdā-​shnəl How to pronounce aggradational (audio) , -​shə-​nᵊl \ adjective

Examples of aggradation in a Sentence

Recent Examples on the Web Number one is aggradation of the channel bed, and number two, a mega flood. Mark Schleifstein,, "Rising river bottom could switch Mississippi to Atchafalaya riverbed in next mega flood," 12 Dec. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'aggradation.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of aggradation

1898, in the meaning defined above

History and Etymology for aggradation

aggrade "to fill with detrital material, build up by aggradation" (from ad- + -grade, as in degrade) + -ation (after degradation)

Note: Aggrade and aggradation were apparently introduced by the geologist Rollin D. Salisbury in Surface Geology: Report of Progress, from the Annual Report of the State Geologist for 1892, Trenton, N.J.: Geological Survey of New Jersey, 1893, p. 103.

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Time Traveler for aggradation

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The first known use of aggradation was in 1898

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Cite this Entry

“Aggradation.” Dictionary, Merriam-Webster, Accessed 27 Sep. 2020.

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