★ If someone says "all y’all," they’re either stressing the point or talking to every last one of you. ★
Origin
Contraction of "you all," dating back to at least the early 19th century in Southern American English. Variants like "youse" and "youns" trace back to Scots-Irish and other immigrant dialects.
Notes
"Y’all" is strictly plural for many speakers, though in some areas it’s used for one person in friendly conversation. Forms like "all y’all" add emphasis, and variants such as "youns" are found in certain Appalachian communities.
Y’all - /jʌɑl/ standard plural "you" (pronoun)
Y’all's /jʌ.ɑlz/ - possessive form ("Is this y’all’s car?")
Y’alls's /jʌɑlzəz/ - possessive form ("Is this y’alls's house?")
Created by The Hillbilly Dude, this site is a growing field guide to culture, speech, memory, and meaning - rooted in Appalachia but reaching across the world. Every slang word, saying, accent and story is gathered from first-hand experience and trusted sources. The goal: preserve authentic voices and share them with writers, learners, and culture lovers everywhere - with a little humor thrown in here and there. Read more...
I use 'y’all' pretty much daily, and so do most around here. As for using y’all for a single person? I've only seen that on televisions and in movies.