Answer:

plateaus

Answer	Crossword Clue
PLATEAUS	Levels off
PLATEAUS	Grand Canyon vistas
PLATEAUS	Flattens out

PLATEAUS	Flattens
PLATEAUS	Tablelands
PLATEAUS	Reaches one's limit
PLATEAUS	Flat extents in a graph.
PLATEAUS	Mesas
PLATEAUS	Flat dishes, as for tea service
PLATEAUS	High spots
PLATEAUS	Starts to stagnate

PLATEAUS	Achievement levels
PLATEAUS	Attainment levels