verb (used with object), ag·grad·ed, ag·grad·ing. Physical Geography.
  1. to raise the grade or level of (a river valley, a stream bed, etc.) by depositing detritus, sediment, or the like.
Compare degrade.

Origin of aggrade

First recorded in 1895–1900; ag- + grade
Related formsag·gra·da·tion [ag-ruh-dey-shuh n] /ˌæg rəˈdeɪ ʃən/, nounag·gra·da·tion·al, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for aggradation

Historical Examples of aggradation

British Dictionary definitions for aggradation


  1. (tr) to build up the level of (any land surface) by the deposition of sedimentCompare degrade (def. 4)
Derived Formsaggradation (ˌæɡrəˈdeɪʃən), noun
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