Alabama

A 1974 rock anthem became shorthand for an accusation nobody spells out.

The words are the title of Lynyrd Skynyrd's 1974 song, itself a defense of the state, but the slang sense turns it around and runs on the stereotype of rural southern families marrying their own. Wiktionary labels this sense slang and humorous and dates its citations from 2019 to 2022: meme pages, an article describing it as an incest joke aimed at southern people, and a post about a dating app matching two siblings. The line is usually aimed at strangers in a photograph rather than at Alabamians directly, though the state supplies the whole premise.