I. pla-ˈtō, ˈpla-ˌ noun
( plural plateaus or pla·teaux -ˈtōz, -ˌtōz)
Etymology: French, from Middle French, platter, from plat flat
Date: 1796
1.
a. : a usually extensive land area having a relatively level surface raised sharply above adjacent land on at least one side : tableland
b. : a similar undersea feature
2.
a. : a region of little or no change in a graphic representation
b. : a relatively stable level, period, or condition
3. : a level of attainment or achievement
the 500-point plateau
II. intransitive verb
Date: 1939
: to reach a level, period, or condition of stability or maximum attainment