This is the 10676th most frequent French word.
montagneuses
Mountainous.
The word 'montagneuses' is used as an adjective modifying 'régions', describing areas with characteristics of having mountains.
Les régions montagneuses sont souvent difficiles d'accès.
Mountainous regions are often difficult to access.
Here, 'montagneuses' depicts the type of zones being described, emphasizing that they are in mountain terrain.
La flore des zones montagneuses est riche et variée.
The flora of mountainous areas is rich and varied.
In this use case, 'montagneuses' modifies 'paysages', giving them the property of having mountains.