Merriam-Webster Collegiate Dictionary - la

 I. abbreviation Louisiana  II. symbol lanthanum LA  I. interjection  Etymology: Middle English (northern dialect), from Old English la  Date: before 12th century chiefly dialect — used for emphasis or expressing surprise  II. noun  Etymology: Middle English, from Medieval Latin, from the syl~ble sung to this note in a medieval hymn to Saint John the Baptist  Date: 14th century the sixth tone of the diatonic scale in solmization LA  abbreviation  1. law agent  2. legislative assistant  3. Los Angeles  4. Louisiana