1. In geography, a tract of land having or considered to have certain natural features and characteristics: The terrain possessed adequate physical characteristics for military purposes.
2. Etymology: from Latin terranum, terrenum, "land, ground"; from terrenus, "of earth, earthly"; from terra, "earth, land"; literally, "dry land" (as opposed to the "sea"); from Greek teresesthai, "to become dry" or "to be dry"; Latin torrere "to dry up, to parch".