mountainous

adjective4

1. •
   Having many mountains; characterized by mountains; of the nature of a mountain; rough (terrain); rocky.
2. •
   Resembling a mountain, especially in size; huge; towering.

   • But the added size did not give them an advantage this time. Not when Kanter and Adams, two mountainous players, could match the Knicks’ girth with their own. — 2016
3. •
   (figurative) Very difficult.
4. •
   (no longer used) Inhabiting mountains; hence, barbarous.