A region of the United States covering the geographic southern United States, or roughly the area south of the 37th or 38th parallels, north latitude.
Not to be confused with the Bible Belt, the Sun Belt extends beyond the states traditionally associated with the deep south (Georgia, Alabama, Mississippi, Louisiana, Arkansas, Kentucky, Tennessee, and the Carolinas), and extends west through the warmer climes of the continental U.S. (Texas, New Mexico, Arizona, California, Florida, Colorado, Utah, Oklahoma, Nevada, extending as far north as Virginia).
The Sun Belt has seen substantial population growth in recent decades, fueled by milder winters, coupled with the availability and affordability of air conditioning. In addition, the latter half of the 20th century has seen a surge in retiring baby boomers migrating domestically, as well as the influx of immigrants, both legal and illegal, into this region.
One of the most densely populated areas for professional sports in the U.S., the college powerhouse SEC has existed there for over 75 years, with the population boom also adding to the creation of the eponymous Sun Belt Conference (est. 1976) and the currently higher profile Conference USA (est. 1995). All three conferences exist entirely within this region.
Tony: Man, it's too crowded out here in New York, I don't even have room to think.
Andrea: I know it ain't for everyone, but my cousins moved down to the Sun Belt and they couldn't be happier.
Tony: Sun Belt? Is that like the Bible Belt?
Andrea: Naw, the Bible Belt is mostly conservative country folk. The urban population is exploding down there with new liberal voters, and Obama even carried Houston in 2008, not to mention all of New Mexico.