[loo-si-tey-nee-uh] 
| 1. | (italics ) a British luxury liner sunk by a German submarine in the North Atlantic on May 7, 1915: one of the events leading to U.S. entry into World War I. |
| 2. | an ancient region and Roman province in the Iberian Peninsula, corresponding generally to modern Portugal. |
| Lu·si·ta·ni·a (lōō'sĭ-tā'nē-ə) An ancient region and Roman province of the Iberian Peninsula. It corresponded roughly to modern-day Portugal. Lu'si·ta'ni·an adj. & n. |
A British passenger ship sunk by a German submarine off the coast of Ireland in 1915. Germany, then at war with Britain but not with the United States (see World War I), had warned Americans against traveling on the ship. More than a hundred Americans died in the sinking. The incident worsened relations between Germany and the United States and encouraged American involvement in the war.