Terr (earth, land)
Terr
Latin terra: earth, land.
The jeep crossed rocky terrain in Ladakh.
Terrain
An area of land and what its surface is like.
Hilly terrain makes cycling in Coorg hard work.
Terrace
A flat area of land or roof, or a step on a hillside.
Tea grows on green terraces in the hills of Darjeeling.
Remember: Terr = land: terrestrial, subterranean (under the land), the Mediterranean ('middle of the land'). Caution: terrible and terror come from Latin terrere (to frighten), not terra.