This is the 9755th most frequent Portuguese word.
declive
A slope or incline.
In this sentence, 'declive' is used to designate a physical feature, namely the slanted or sloping area of a road.
O carro desceu pelo declive da estrada e foi difícil parar.
The car went down the slope of the road and it was hard to stop.
Here, 'declive' metaphorically indicates a reduction or decrease, such as in production levels.
Há um declive na produção industrial devido à crise econômica.
There is a decline in industrial production due to the economic crisis.
The word 'declive' again refers to a physical slope, yet specifies the nature of the slope as gentle or moderate.