Is it ensure, insure, or assure?
A political leader of the late eighteenth and early nineteenth centuries; one of the Founding Fathers; the leader of the Democratic-Republican party. Jefferson was principal author of the Declaration of Independence and served as president from 1801 to 1809, between John Adams and James Madison. He arranged for the Louisiana Purchase, founded the University of Virginia, and built the mansion Monticello. Jefferson is famed as a champion of political and religious freedom, but he was also a slaveholder. (See Jeffersonian democracy; Sally Hemings.)