[ pla-toh or, especially British, plat-oh ]
See synonyms for: plateauplateaus on

noun,plural pla·teaus, pla·teaux [pla-tohz or, especially British, plat-ohz]. /plæˈtoʊz or, especially British, ˈplæt oʊz/.
  1. a land area having a relatively level surface considerably raised above adjoining land on at least one side, and often cut by deep canyons.

  2. a period or state of little or no growth or decline: to reach a plateau in one's career.

  1. Psychology. a period of little or no apparent progress in an individual's learning, marked by an inability to increase speed, reduce number of errors, etc., and indicated by a horizontal stretch in a learning curve or graph.

  2. a flat stand, as for a centerpiece, sometimes extending the full length of a table.

verb (used without object),pla·teaued, pla·teau·ing.
  1. to reach a state or level of little or no growth or decline, especially to stop increasing or progressing; remain at a stable level of achievement; level off: After a period of uninterrupted growth, sales began to plateau.

verb (used with object),pla·teaued, pla·teau·ing.
  1. to cause to remain at a stable level, especially to prevent from rising or progressing: Rising inflation plateaued sales income.

Origin of plateau

1785–95; <French; Old French platel flat object, diminutive of platplate1 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use plateau in a sentence

British Dictionary definitions for plateau (1 of 2)


/ (ˈplætəʊ) /

nounplural -eaus or -eaux (-əʊz)
  1. a wide mainly level area of elevated land

  2. a relatively long period of stability; levelling off: the rising prices reached a plateau

  1. to remain at a stable level for a relatively long period

Origin of plateau

C18: from French, from Old French platel something flat, from plat flat; see plate

British Dictionary definitions for Plateau (2 of 2)


/ (ˈplætəʊ) /

  1. a state of central Nigeria, formed in 1976 from part of Benue-Plateau State: tin mining. Capital: Jos. Pop: 3 178 712 (2006). Area: 30 913 sq km (11 936 sq miles)

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

Scientific definitions for plateau


[ plă-tō ]

  1. An elevated, comparatively level expanse of land. Plateaus make up about 45 percent of the Earth's land surface.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.