"Terra firma" History & Related English words Related English words include terrain, terrestrial and territory, root words of terra. The term is often used when describing the long voyages of explorers and sailors. Christopher Columbus, fearing mutiny, must have been extremely relieved to sight land (terra firma) on October 12, 1492 after 70 days at sea. Another couple of famous expressions during the golden Age of Exploration is 'Terra incognita' meaning "unknown land" which was used in cartography for areas that had not been mapped or documented. The term 'mare incognitum' that means "unknown sea" and was used in reference to uncharted seas . |