nouninformal, derogatory US
As a mass noun or in plural. Originally in the language of African Americans of the southern United States: poor white people of low social status, especially when regarded as uneducated or uncultured.
poor white folk/ˌpɔː ˈwʌɪt fəʊk/ /ˌpʊə ˈwʌɪt fəʊk/
Early 19th century; earliest use found in Port Folio. From poor white + folk, after white folks.