Demonym: Angeleno (an-juh-LEE-no). From Spanish ángel — "angel." Short for the 1781 pueblo name: El Pueblo de Nuestra Señora la Reina de los Ángeles de Porciúncula. "Angeleno" appeared in English newspapers by the 1850s; "Angelenian" never stuck.
Pronunciation note: locals say AN-juh-lee-no (three syllables, stress first). Outsiders often say an-juh-LEE-no. Both accepted; the first marks you as de aquí.