From Dictionary.com:
(sometimes it's embarrassing to speak American)
American Heritage Dictionary - Cite This Source
you-all (yōō'ôl')
pron. Chiefly Southern U.S.
You. Used in addressing two or more people or referring to two or more people, one of whom is addressed.
The single most famous feature of Southern United States dialects is the pronoun
y'all, sometimes heard in its variant
you-all. You-all functions with perfect grammatical regularity as a second person plural pronoun, taking its own possessive you-all's (or less frequently, your-all's, where both parts of the word are inflected for possession): You-all's voices sound alike. Southerners do not, as is sometimes believed, use you-all or y'all for both singular and plural you. A single person may only be addressed as you-all if the speaker implies in the reference other persons not present: Did you-all [you and others] have dinner yet? You and you-all preserve the singular/plural distinction that English used to have in thou and ye, the subject forms of singular and plural you, respectively (thee and you were the singular and plural object forms). The distinction between singular thou/thee and plural ye/you began to blur as early as the 13th century, when the plural form was often used for the singular in formal contexts or to indicate politeness, much as the French use tu for singular and familiar "you," and vous for both plural and polite singular "you." In English, the object form you gradually came to be used in subject position as well, so that the four forms thou, thee, ye, and you collapsed into one form, you. Thou and thee were quite rare in educated speech in the 16th century, and they disappeared completely from standard English in the 18th. However, the distinction between singular and plural you is just as useful as that between other singular and plural pronoun forms, such as I and we. In addition to y'all,
other forms for plural you include you-uns, youse, and you guys or youse guys. Youse is common in vernacular varieties in the Northeast, particularly in large cities such as New York and Boston, and is also common in Irish English.
You-uns is found in western Pennsylvania and in the Appalachians and probably reflects the Scotch-Irish roots of many European settlers to these regions. You guys and youse guys appear to be newer innovations than the other dialectal forms of plural you. See Note at you-uns.
(Download Now or Buy the Book)
The American Heritage® Dictionary of the English Language, Fourth Edition
Copyright © 2006 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.