Pronunciation: (bä'hä kal"u-fôr'nyu, -fôr'nē-u; Sp. bä'hä kä"lē-fôr'nyä),[key] a narrow peninsula in NW Mexico between the Gulf of California and the Pacific, forming two territories of Mexico. 1,434,000; 55,634 sq. mi. (144,090 sq. km). Caps: Mexicali (Northern Territory) and La Paz (Southern Territory). Also called Ba'ja, Lower California.