Having many mountains; characterized by mountains; of the nature of a mountain; rough (terrain); rocky. / Resembling a mountain, especially in size; huge; towering.

In a mountainous manner.

The quality of being mountainous.

(countable) An elevation of land of considerable dimensions rising more or less abruptly, forming a conspicuous figure in the landscape, usually having a small extent of surface at its summit.

plural of mountain / mountain range

The sport of climbing mountains.

(intransitive) To climb mountains; to climb using the techniques of a mountaineer. / (intransitive, figuratively) To climb as if on a mountain.

(now rare) A person who lives in a mountainous area (often with the connotation that such people are outlaws or uncivilized). / A person who climbs mountains for sport or pleasure.

plural of mountaineer

plural of Mountain