ˌLewis and ˈClark
two explorers, Meriwether Lewis(1774–1809) and William Clark (1770–1838), who travelled across North America from 1804 to 1806, going up the Missouri River and over the Rocky Mountains to the Pacific coast. They drew maps and gathered information about the Native American people who lived there.

[TahlilGaran] Dictionary of Contemporary English ▲