Area of the US that includes all of Arizona and New Mexico. Also some of California, Texas, Nevada, Utah, Colorado, and Oklahoma.
Southwest cities include Phoenix, Houston, Dallas, Denver, Salt Lake City, San Antonio, Tucson, Albuquerque, El Paso, and Las Vegas.
Easterner: "Good Lord, it's so fucken hot in the Southwest."
Father: "Hey Kids we're going on vacation to see the American Southwest! We'll be visiting the Grand Canyon, Monument Valley, the mountains of Colorado, the deserts and cacti of Arizona, the heat of Nevada, the mormons of Utah, the aliens of New Mexico, the cowboys of Texas, the fun of California and...and...it'll be fun!"
Kids: "Oh cool we're going to Vegas then! Woo hoo!"