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definitions

thy

[th ahy]
|

pronoun

the possessive case of thou (used as an attributive adjective before a noun beginning with a consonant sound): thy table.
Compare thine.

Origin of thy

1125–75; Middle English; variant of thine

thou

1
[th ou]

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
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for thy

Contemporary Examples of thy

Historical Examples of thy

  • Why wast thou, so richly gifted of the gods, to be taken from us in thy youth?

    Philothea

    Lydia Maria Child

  • If it were not so, his hand would have written in reply to thy kind epistle.

    Philothea

    Lydia Maria Child

  • “One of thy old doctors in barnacles, I trow,” said Stephen.

    The Armourer's Prentices

    Charlotte M. Yonge

  • But the word is very nigh unto thee, in thy mouth and in thy heart.

  • But the margin has it "of thy servant," which does not agree with the person of the verb.

British Dictionary definitions for thy

thy

determiner

(usually preceding a consonant) archaic belonging to or associated in some way with you (thou)thy goodness and mercy Compare thine

Word Origin for thy

C12: variant of thine

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 thy
pron.

possessive pronoun of 2nd person singular, late 12c., reduced form of þin (see thine), originally used before consonants except -h-. In 15c., used before vowels, too.

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