1. terrain
It has four-wheel drive and can travel on any terrain.
It's crazy how much uncharted terrain is down here.
The rough terrain checked the progress of the hikers.
But China's extreme terrain and size have created...
Boeing's safety experts have joined others in the industry to form an international task force to try to eliminate one particular kind of air crash known as controlled flight into terrain, CFIT.
When warm, light, air crosses mountains it rises into the upper atmosphere and does not fall back to the ground. In this, and other, ways wind changes with the terrain.
This is awfully hilly terrain; I hope we don't screw up the transmission.