Bahrain or Bahrein (both: bärān', bu–) [key], officially Kingdom of Bahrain, constitutional monarchy and archipelago (2005 est. pop. 688,300), 266 sq mi (689 sq km), in the Persian Gulf. The two main islands are Bahrain and Al Muharraq, connected by a causeway. The capital and chief port is Al Manamah, on Bahrain.
