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thou

1 American  
[thou] / ðaʊ /

pronoun

singular

thou,

possessive

thy, thine,

objective

thee,

plural

you, ye,

possessive

your, yours,

objective

you, ye
  1. Archaic except in some elevated or ecclesiastical prose. the second person singular subject pronoun, equivalent to modern you (used to denote the person or thing addressed).

    Thou shalt not kill.

  2. (used byQuakers ) a familiar form of address of the second person singular.

    Thou needn’t apologize.


verb (used with object)

  1. to address as “thou,” especially during an era of historical English when “thou” was distinguished as an informal form of you.

    It would have been scandalous for household staff to thou the lord of the manor.

verb (used without object)

  1. to use “thou” in discourse.

    There are still Quakers who thou as a matter of custom.

thou 2 American  
[thou] / θaʊ /

noun

Slang.

plural

thous,

plural

thou
  1. one thousand dollars, pounds, etc.


thou 1 British  
/ ðaʊ /

pronoun

  1. archaic refers to the person addressed: used mainly in familiar address or to a younger person or inferior

  2. (usually capital) refers to God when addressed in prayer, etc

"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

thou 2 British  
/ θaʊ /

noun

  1. one thousandth of an inch. 1 thou is equal to 0.0254 millimetre

  2. 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

Etymology

Origin of thou1

First recorded 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, Old Church Slavonic ty; akin to Sanskrit tvam; (verb) late Middle English thowen, derivative of the pronoun

Origin of thou2

First recorded in 1865–70; by shortening

Explanation

The word thou, used in place of "you," is not used much in modern language. In fact, with its Biblical feeling, it’s most often used in religious contexts. Otherwise, it might be used as slang for thousand. Anyone familiar with the Bible knows the word thou means "you." As the word worked its way from Old English, it varied a little in its subtext, from a plural referring to higher-ups, then to equals, and, around 1450, as a slightly insulting reference suggesting inferiority. Today, it's used primarily by specific religious groups, or as a somewhat affected, archaic word in poetry. As a side note, if someone asks you for a thou, they mean a thousand dollars.

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Ecclesiastes 11:1: “Cast thy bread upon the waters: for thou shalt find it after many days.”

From MarketWatch • Apr. 7, 2026

Some referred to the commandment "thou shalt not kill".

From BBC • May 13, 2025

“When I do it, I'm trying not to be holier than thou in every way that I can. And I fail at that a fair amount.”

From Salon • Nov. 4, 2024

When I consider thy heavens, the work of thy fingers, the moon and the stars, which thou hast ordained; what is man, that thou art mindful of him?

From Los Angeles Times • Aug. 21, 2024

“Take thy rest for now, and thou wilt do better work next time. Here is Brother Luke coming to care for thee. I shall not tell him how nearly I lost my head.”

From "The Door in the Wall" by Marguerite de Angeli