The word thou (pronounced IPA ) was a second person singular pronoun in English. It is now largely archaic, having been replaced in almost all contexts by you. Thou is the nominative form; the oblique/objective form is thee (functioning as both accusative and dative), and the possessive is thy or thine. Almost all verbs following thou have the endings -st or -est; e.g., "thou goest". In Middle English, thou was sometimes abbreviated by putting a small "u" over the letter thorn: .
Originally, thou was simply the singular counterpart to the plural pronoun ye, derived from an ancient Indo-European root. In imitation of continental practice, thou was later used to express intimacy, familiarity, or even disrespect while another pronoun, you, the oblique/objective form of ye, was used for formal circumstances (see T-V distinction). After thou fell out of fashion, it was primarily retained in fixed ritual settings, so that for some speakers, it came to connote solemnity or even formality. Thou persists, sometimes in altered form, in regional dialects of England and Scotland. In standard modern English, however, thou continues to be used only in religious contexts, in literature that seeks to capture an archaic sense of formality, and in certain fixed phrases such as "holier than thou" and "fare thee well". The disappearance of the singular-plural distinction has been compensated for through the use of neologisms in various dialects. Colloquial American English, for example, contains plural constructions that vary regionally, including y'all, youse, and you guys.