1/ðaʊ/Show Spelled Pronunciation[thou]Show IPA,pronoun, singular, nominative thou;possessive thy or thine;objective thee;plural, nominative you or ye;possessive your or yours;objective you or ye;verb
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.
2.
(used by the Friends) a familiar form of address of the second person singular.
–verb (used with object)
3.
to address as “thou.”
–verb (used without object)
4.
to use “thou” in discourse.
Origin: bef. 900; ME; OE thū; c. G, MD du, ON thū, Goth thu, OIr tú, Welsh, Cornish ti, L tū, Doric Gk tý, Lith tù, OCS ty; akin to Skt tvam; (v.) late ME thowen, deriv. of the pronoun
[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; verb