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definitions

thou

1
[th ou]
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pronoun, singular, nominative thou; possessive thy or thine; objective thee; plural, nominative you or ye; possessive your or yours; objective you or ye.

Archaic except in some elevated or ecclesiastical prose. the personal pronoun of the second person singular in the nominative case (used to denote the person or thing addressed): Thou shalt not kill.
(used by the Friends) a familiar form of address of the second person singular.

verb (used with object)

to address as “thou.”

verb (used without object)

to use “thou” in discourse.

Origin of thou

1
before 900; Middle English; Old English thū; cognate with German, Middle Dutch du, Old Norse thū, Gothic thu, Old Irish tú, Welsh, Cornish ti, Latin tū, Doric Greek tý, Lithuanian tù, OCS ty; akin to Sanskrit tvam; (v.) late Middle English thowen, derivative of the pronoun

thou

2
[thou]

noun, plural thous, (as after a numeral) thou. Slang.

one thousand dollars, pounds, etc.

Origin of thou

2
First recorded in 1865–70; by shortening
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for thou

Contemporary Examples of thou

Historical Examples of thou

  • "Stranger, thou hast not yet learned the fashions of Athens," said Anaxagoras, gravely.

    Philothea

    Lydia Maria Child

  • I fly to seek a kindlier sphere, Since thou hast ceased to love me here.

    Philothea

    Lydia Maria Child

  • “Thou art a big fellow for a school,” said his uncle, looking him over.

    The Armourer's Prentices

    Charlotte M. Yonge

  • “Thou art a good-hearted lad,” said the alderman with a hand on his shoulder.

    The Armourer's Prentices

    Charlotte M. Yonge

  • “Thou shouldst bring him one of these days,” said Sir Thomas.

    The Armourer's Prentices

    Charlotte M. Yonge

British Dictionary definitions for thou

thou

1

pronoun (subjective)

archaic, dialect refers to the person addressed: used mainly in familiar address or to a younger person or inferior
(usually capital) refers to God when addressed in prayer, etc

Word Origin for thou

Old English thū; related to Old Saxon thū, Old High German du, Old Norse thū, Latin tū, Doric Greek tu

thou

2

noun plural thous or thou

one thousandth of an inch. 1 thou is equal to 0.0254 millimetre
informal short for thousand
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for thou
pron.

2nd nominative singular personal pronoun, Old English þu, from Proto-Germanic *thu (cf. Old Frisian thu, Middle Dutch and Middle Low German du, Old High German and German du, Old Norse þu, Gothic þu), from PIE *tu-, second person singular pronoun (cf. Latin tu, Irish tu, Welsh ti, Greek su, Lithuanian tu, Old Church Slavonic ty, Sanskrit twa-m).

Superseded in Middle English by plural form you (from a different root), but retained in certain dialects (e.g. Philadelphia Quakers). The plural at first was used in addressing superior individuals, later also (to err on the side of propriety) strangers, and ultimately all equals. By c.1450 the use of thou to address inferiors gave it a tinge of insult unless addressed by parents to children, or intimates to one another. Hence the verb meaning "to use 'thou' to a person" (mid-15c.).

Avaunt, caitiff, dost thou thou me! I am come of good kin, I tell thee! ["Hickscorner," c.1530]

A brief history of the second person pronoun in English can be found here.

Online Etymology Dictionary, © 2010 Douglas Harper