“Who’s” is a form of
who
UK /huː/ · US /hu/ pronoun, noun, determiner, proper noun
Forms whom whose whos the WHO W.H.O. W. H. O.
- pronoun (interrogative) What person or people; which person or people; asks for the identity of someone; used in a direct or indirect question. “Who says they care? —They themselves do.”
- pronoun With antecedent as subject.
- pronoun (non-formal) With antecedent as object: whom. “That's the man who I saw earlier.”
- pronoun (fused relative, archaic or marginal) Whoever, he who, they who. “Who dares wins.”
- pronoun (informal, especially non-US) Also used with names of collective nouns that are groups of people, especially singularly-named musical groups or sports teams. “Who are the Miami Heat?”
- noun A person under discussion; a question of which person.
- determiner (interrogative, dialect, African-American Vernacular) whose “Who phone just rang?”
- proper noun (fandom slang) The television show Doctor Who.
Synonyms
Etymology
From Middle English who, hwo, huo, wha, hwoa, hwa, from Old English hwā (dative hwām, genitive hwæs), from Proto-West Germanic *hwaʀ, from Proto-Germanic *hwaz, from Proto-Indo-European *kʷos, *kʷís.
The sound change /hw/ > /h/ (without a corresponding change in spelling) was due to wh-cluster reduction after an irregular change of /ɑː/ to /oː/ in Middle English (instead of the expected /ɔː/) and further to /uː/ regularly in Early Modern English. A similar change occurred in two. Compare how, which underwent wh-reduction earlier (in Old English), and thus is spelt with h.
Compare Scots wha, West Frisian wa, Dutch wie, Low German we, German wer, Swedish vem, Danish hvem, Norwegian Bokmål hvem, Norwegian Nynorsk kven, Icelandic hver.
Webster’s 1913
- pronoun Originally, an interrogative pronoun, later, a relative pronoun also; --used always substantively, and either as singular or plural.
- pronoun One; any; one. [Obs., except in the archaic phrase, as who should say.]
Etymology [OE. who, wha, AS. hwa, interrogative pron., neut. hwæt; akin to OFries. hwa, neut. hwet, OS. hwe, neut. hwat, D. wie, neut. wat, G. wer, neut.was, OHG. wer, hwer, neut. waz, hwaz, Icel. hvat, neut., Dan. hvo, neut. hvad, Sw. ho, hvem, neut. hvad, Goth. hwas, fem. hwo, neut. hwa, Lith. kas, Ir. & Gael. co, W. pwy, L. quod, neuter of qui, Gr. po`teros whether, Skr. kas. sq. root182. Cf. How, Quantity, Quorum, Quote, Ubiquity, What, When, Where, Whether, Which, Whither, Whom, Why.]
Sources: Wiktionary · WordNet 3.0 · Webster’s 1913 — from the Wiktionary entry “who”, CC BY-SA 4.0. Details