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 (wī, hwī)
For what purpose, reason, or cause; with what intention, justification, or motive: Why is the door shut? Why do birds sing?
1. The reason, cause, or purpose for which: I know why you left.
2. Usage Problem On account of which; for which.
n. pl. whys
1. The cause or intention underlying a given action or situation: studying the whys of antisocial behavior.
2. A difficult problem or question.
Used to express mild surprise, indignation, or impatience.

[Middle English, from Old English hwȳ; see kwo- in Indo-European roots.]
Usage Note: A traditional rule states that why is redundant in the expression reason why, as in The reason why he accepted the nomination is not clear. It is true that why could be eliminated from such examples with no loss to the meaning, and that that could be used instead of why, but reason why has been used by reputable English writers since the Renaissance, and a majority of the Usage Panel accepts the construction. In our 2009 survey, 55 percent accepted the example quoted above. Higher percentages accepted examples in which reason is modified by a, any, or another instead of the.. For instance, 67 percent accepted the example Is there any reason why this drug enforcement program should work? While there is certainly no harm in observing this rule in one's own writing, insisting on it in the writing of others may seem petty. See Usage Note at where.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


a. for what reason, purpose, or cause?: why are you here?.
b. (used in indirect questions): tell me why you're here.
for or because of which: there is no reason why he shouldn't come.
n, pl whys
(usually plural) the reason, purpose, or cause of something (esp in the phrase the whys and wherefores)
an introductory expression of surprise, disagreement, indignation, etc: why, don't be silly!.
[Old English hwī; related to Old Norse hvī, Gothic hveileiks what kind of, Latin quī]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ʰwaɪ, waɪ)

adv., conj., n., pl. whys,
interj. adv.
1. for what? for what reason or purpose?: Why do you ask?
2. for what cause or reason: I don't know why he left.
3. for which; on account of which (usu. after reason to introduce a relative clause): the reason why she refused to go.
4. the reason for which: That is why he returned.
5. a question concerning the cause or reason for which something is done, achieved, etc.: a child's unending whys.
6. the cause or reason: the whys and wherefores of the Cold War.
7. (used as an expression of surprise, hesitation, etc., or sometimes a mere expletive): Why, it's all gone!
[before 900; Middle English; Old English hwī, hwȳ, instr. case of hwæt what; c. Old Norse hvī]
usage: See reason.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


1. used in questions

You use why when you are asking a question about the reason for something.

'I had to say no.' – 'Why?'
Why did you do it, Marta?
2. used when no answer is expected

You sometimes use why in questions without expecting an answer. For example, you can make a suggestion by asking a question beginning with Why don't.

Why don't we all go?
Why don't you write to her yourself?

You can emphasize that there is no reason for something to be done by asking a question beginning with Why should.

Why would he be angry with you?
'Will you say sorry?' – 'No, why should I?'

You can emphasize that there is no reason why something should not be done by asking a question beginning with Why shouldn't.

Why shouldn't he go to college?

You can suggest that an action is pointless by using why followed by an infinitive without to.

Why tell the police? It won't do any good.
3. used in reported clauses

Why is often used in reported clauses.

He wondered why she had come.
You never really told me why you don't like him.

Why can be used on its own instead of a reported clause, if it is clear what you mean. For example, instead of saying 'She doesn't like him. I don't know why she doesn't like him', you can say 'She doesn't like him, I don't know why'.

They refuse to come – I don't know why.
He's certainly cheerful, though I can't think why.
4. used in relative clauses

Why is sometimes used in relative clauses with the word reason.

That is one reason why they were such a successful team.
See reason
Collins COBUILD English Usage © HarperCollins Publishers 1992, 2004, 2011, 2012
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.why - the cause or intention underlying an action or situation, especially in the phrase `the whys and wherefores'
reason, ground - a rational motive for a belief or action; "the reason that war was declared"; "the grounds for their declaration"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.


1. That which provides a reason or justification:
Idiom: why and wherefore.
2. A fact or circumstance that gives logical support to an assertion, claim, or proposal:
argument, ground (often used in plural), proof, reason, wherefore.
Idiom: why and wherefore.
3. What one intends to do or achieve:
Idioms: end in view, why and wherefore.
The American Heritage® Roget's Thesaurus. Copyright © 2013, 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ضَمير صِلَه بِمَعْنى: الذي بِسَبَبِهلـِمَاذالماذا؟
ami miattmiért
af hverjuaf hverju, hvers vegnaástæðahvers vegna, af hverju
niçinniye-in sebebi/nedenineden
tại saovì saosao


A. ADVpor qué
why not?¿por qué no?
why on earth didn't you tell me?¿por qué demonios no me lo dijiste?
I know why you did itpor qué lo hiciste
why he did it we shall never knowno sabremos nunca por qué razón lo hizo
that's why I couldn't comepor eso no pude venir
which is why I am hereque es por lo que estoy aquí
B. EXCL¡toma!, ¡anda!
why, it's you!¡toma, eres tú!, ¡anda, eres tú!
why, what's the matter?bueno, ¿qué pasa?
why, there are 8 of us!¡si somos 8!
why, it's easy!¡vamos, es muy fácil!
C. N the whys and (the) whereforesel porqué
 Why can usually be translated by por qué:
Why didn't you come? ¿Por qué no viniste? They asked her why she hadn't finished her report Le preguntaron por qué no había terminado el informe
! Remember the difference in spelling between por qué (why) and porque (because).
 To ask specifically about the purpose of something, you can translate why using para qué:
Why go if we are not needed? ¿Para qué vamos a ir si no nos necesitan?
 In statements, you can translate (the reason) why using por qué, la razón (por la que) or el motivo (por el que):
Tell me (the reason) why you don't want to accept the proposal Dime por qué or la razón por la que or el motivo por el que no quieres aceptar la propuesta
 Translate that's why using por eso:
That's why they wouldn't pay Por eso no querían pagar
 Like all question words in Spanish, porqué can function as a masculine noun. Note that in el porqué, porqué is written as one word:
I'd like to know why he's absent or the reason for his absence Me gustaría saber el porqué de su ausencia
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005


adv (in questions)pourquoi
Why did you do that? → Pourquoi avez-vous fait ça?
Why is he late? → Pourquoi est-il en retard?
Tell me why → Dis-moi pourquoi.
I've never been to France. - Why not? → Je ne suis jamais allé en France. - Pourquoi?
All right, why not? → D'accord, pourquoi pas?
(in relative clauses)pourquoi
That's why he did it → Voilà pourquoi il a fait ça.
the reason why sb did sth → la raison pour laquelle qn a fait qch
She never told me the reason why she left → Elle ne m'a jamais dit pourquoi elle était partie.
She left, and nobody knows the reason why → Elle est partie et personne ne sait pourquoi.
excl (= well!) → tiens!
Collins English/French Electronic Resource. © HarperCollins Publishers 2005


advwarum, weshalb; (asking for the purpose) → wozu; (= how come that …)wieso; why not ask him?warum fragst du/fragen wir etc ihn nicht?; why wait?warum or wozu (noch) warten?; why do it this way?warum denn so?; that’s whydarum, deshalb, deswegen; that’s exactly whygenau deshalb or deswegen
interj why, of course, that’s right!ja doch or aber sicher, das stimmt so!; are you sure? — why yes (of course/I think so)sind Sie sicher? — aber ja doch; why that’s easy!na, das ist doch einfach!; take the bus! why, it’s only a short walkden Bus nehmen? ach was, das ist doch nur ein Katzensprung; why, if it isn’t Charles!na so was, das ist doch (der) Charles!; who did it? why it’s obviouswer das war? na or also, das ist doch klar
n the whys and (the) whereforesdas Warum und Weshalb
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007


1. adv & conjperché
why is he always late? → perché è sempre in ritardo?
I wonder why he said that → mi chiedo perché l'abbia detto
why not do it now? → perché non farlo adesso?
why don't you come too? → perché non vieni anche tu?
there's no reason why ... → non c'è motivo per cui...+ sub
why (ever) not? → perché no?
so that's why he did it! → ecco perché l'ha fatto!
2. excl (surprise) → guarda guarda!, ma guarda un po'!; (remonstrating) → ma via!; (explaining) → ebbene!
why, it's you! → guarda guarda, or ah sei tu!
why, it's obvious! → ma via, è ovvio!
3. n the whys and (the) whereforesle ragioni or i motivi
the why and the how → il perché e il percome
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995


(wai) adverb
for which reason (?). `Why did you hit the child?'; `He hit the child.' `Why?'; Why haven't you finished?; `I haven't finished.' `Why not?'; `Let's go to the cinema.' `Why not?' (= Let's!); Tell me why you came here.
relative pronoun
for which. Give me one good reason why I should help you!
Kernerman English Multilingual Dictionary © 2006-2013 K Dictionaries Ltd.


لـِمَاذا proč hvorfor warum γιατί por qué miksi pourquoi zašto perché なぜ waarom hvorfor dlaczego por que motivo, Porquê? почему varför ทำไม niçin tại sao 为什么
Multilingual Translator © HarperCollins Publishers 2009
References in classic literature ?
I was in such an irritated frame of mind that in rude and abrupt fashion I blurted out a question as to "why our Marquis de Griers had ceased to accompany her for strolls, or to speak to her for days together."
"Yes-- and I suppose you want to know why," she replied with dry captiousness.
"Then why have you written all this?" you will say to me.
The stupid ones die like oxen, they know not why. It is quite funny to see.
The embers of the great fire had so far burned themselves out and now glowed so low and duskily that I understood why these conspirators desired a torch.
They inflame one another, and know not why! They tinkle with their pinchbeck, they jingle with their gold.
She never told me why, and I couldn't make it out no way.
Why, if I were a man, I could never care for anyone else after knowing you.
"I am not finessing, and I am not in the least afraid of telling you; but I don't see the slightest reason why I should not have written."
"See here, child, who are you, and why are you speaking to me every day?"
Why had she toyed with the threatening catastrophe?
Tikhon scratched his back with one hand and his head with the other, then suddenly his whole face expanded into a beaming, foolish grin, disclosing a gap where he had lost a tooth (that was why he was called Shcherbaty- the gap-toothed).