plateau >> /plæˈtoʊ/
Definition: [noun] An area of relatively level high ground.
Example: The Khmer Loeu hill tribes live in remote highland areas in the plateaus and mountainous areas on the edges of Cambodia.
Definition: [noun] A state of little or no change following a period of activity or progress.
Example: the peace process had reached a plateau
Definition: [intransitive verb] Reach a state of little or no change after a time of activity or progress.
Example: the industry's problems have plateaued out