- Armand Jean du Ples·sis [ar–mahn zhahn dy ple-see] /arˈmɑ̃ ʒɑ̃ dü plɛˈsi/, Duc de,1585–1642, French cardinal and statesman.
- a river in SE Canada, in Quebec, flowing N from Lake Champlain to the St. Lawrence. 210 miles (340 km) long.
- Armand Jean du Plessis (armɑ̃ ʒɑ̃ dy plɛsi). 1585–1642, French statesman and cardinal, principal minister to Louis XIII and virtual ruler of France (1624–42). He destroyed the power of the Huguenots and strengthened the crown in France and the role of France in Europe