word | | Terrain |
| topped | Yemen | narrow coastal plain backed by flat-topped hills and rugged mountains; dissected upland desert plains in center slope into the desert interior of the Arabian Peninsula |
| transporting | Southern Ocean | ... Current (21,000 km in length) moves perpetually eastward; it is the world's largest ocean current, transporting 130 million cubic meters of water per second - 100 times the flow of all the ... |
| Transylvanian | Romania | central Transylvanian Basin is separated from the Plain of Moldavia on the east by the Carpathian Mountains and separated from the Walachian Plain on the south by the Transylvanian Alps |
| Trench | Pacific Ocean | ... ocean floor in the eastern Pacific is dominated by the East Pacific Rise, while the western Pacific is dissected by deep trenches, including the Mariana Trench, which is the world's deepest |
| Trench | World | the greatest ocean depth is the Mariana Trench at 10,924 m in the Pacific Ocean |
| trenches | Pacific Ocean | ... ocean floor in the eastern Pacific is dominated by the East Pacific Rise, while the western Pacific is dissected by deep trenches, including the Mariana Trench, which is the world's deepest |
| trending | Eritrea | dominated by extension of Ethiopian north-south trending highlands, descending on the east to a coastal desert plain, on the northwest to hilly terrain and on the southwest to flat-to-rolling ... |
| triangular | French Southern and Antarctic Lands | ... of the volcano is a large plateau Ile Saint-Paul (Ile Amsterdam et Ile Saint-Paul): triangular in shape, the island is the top of a volcano, rocky with steep cliffs on ... |
| Tristan | Saint Helena | ... covered by lava flows and cinder cones of 44 dormant volcanoes; ground rises to the east Tristan da Cunha: sheer cliffs line the coastline of the nearly circular island; the flanks of ... |
| Tromelin | French Southern and Antarctic Lands | ... Eparses): atoll, awash at high tide; shallow (15 m) lagoon Europa Island, Glorioso Islands, Juan de Nova Island: low, flat, and sandy Tromelin Island (Iles Eparses): low, flat, sandy; likely volcanic seamount |
| tundra | Norway | glaciated; mostly high plateaus and rugged mountains broken by fertile valleys; small, scattered plains; coastline deeply indented by fjords; arctic tundra in north |
| tundra | Russia | broad plain with low hills west of Urals; vast coniferous forest and tundra in Siberia; uplands and mountains along southern border regions |
| Turkey | Iraq | mostly broad plains; reedy marshes along Iranian border in south with large flooded areas; mountains along borders with Iran and Turkey |
| Ukraine | Ukraine | most of Ukraine consists of fertile plains (steppes) and plateaus, mountains being found only in the west (the Carpathians), and in the Crimean Peninsula in the extreme south |
| underwater | Wake Island | atoll of three low coral islands, Peale, Wake, and Wilkes, built up on an underwater volcano; central lagoon is former crater, islands are part of the rim |
| undulating | Benin | mostly flat to undulating plain; some hills and low mountains |
| undulating | Burkina Faso | mostly flat to dissected, undulating plains; hills in west and southeast |
| undulating | Cote d'Ivoire | mostly flat to undulating plains; mountains in northwest |
| undulating | Falkland Islands (Islas Malvinas) | rocky, hilly, mountainous with some boggy, undulating plains |
| undulating | Kuwait | flat to slightly undulating desert plain |
| undulating | Libya | mostly barren, flat to undulating plains, plateaus, depressions |
| undulating | Mayotte | generally undulating, with deep ravines and ancient volcanic peaks |
| undulating | Navassa Island | raised coral and limestone plateau, flat to undulating; ringed by vertical white cliffs (9 to 15 m high) |
| undulating | Singapore | lowland; gently undulating central plateau contains water catchment area and nature preserve |
| undulating | Somalia | mostly flat to undulating plateau rising to hills in north |
| uninhabited | Samoa | two main islands (Savaii, Upolu) and several smaller islands and uninhabited islets; narrow coastal plain with volcanic, rocky, rugged mountains in interior |