<p><strong>Noun</strong></p><ul><li>a land area having a relatively level surface considerably raised above adjoining land on at least one side, and often cut by deep canyons.</li><li>a period or state of little or no growth or decline: to reach a plateau in one's career.</li><li>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.</li><li>a flat stand, as for a centerpiece, sometimes extending the full length of a table.</li></ul><p><strong>Verb (used without object)</strong></p><ul><li>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.</li></ul><p><strong>Verb (used with object)</strong></p><ul><li>to cause to remain at a stable level, especially to prevent from rising or progressing: Rising inflation plateaued sales income.</li></ul>