the southern states of the USA 
WordReference Random House Learner's Dictionary of American English © 2025
Sun•belt or Sun Belt /ˈsʌnˌbɛlt/USA pronunciation  
n. [sometimes: sunbelt*  countable;
usually singular;
often: the + ~]
WordReference Random House Unabridged Dictionary of American English © 2025usually singular;
often: the + ~]
- Place Namesthe southern and southwestern region of the U.S.
 
Sun•belt 
(sun′belt′),USA pronunciation n. (sometimes l.c.) 
- Place Namesthe southern and southwestern region of the U.S.
 
- 1950–55
 
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