why

adverb
\ˈhwī, ˈwī\

Definition of why 

(Entry 1 of 4)

: for what cause, reason, or purpose why did you do it?

Definition of why (Entry 2 of 4)

1 : the cause, reason, or purpose for which know why you did it that is why you did it

2 : for which : on account of which know the reason why you did it

why

noun
plural whys

Definition of why (Entry 3 of 4)

1 : reason, cause wants to know the whys and wherefores

2 : a baffling problem : enigma

Definition of why (Entry 4 of 4)

used to express mild surprise, hesitation, approval, disapproval, or impatience why, here's what I was looking for

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Synonyms for why

Synonyms: Noun

account, authority, grounds, motive, reason, subject, wherefore

Synonyms: Interjection

ah, aha, come on, fie, indeed, my word, no, pshaw, well, what

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Examples of why in a Sentence

Adverb

Why did you quit your job? Why is the sky blue? Why didn't you call me? Why didn't I think of that? “I can't go out tonight.” “Why not?”

Conjunction

I know why he did it. It's easy to see why she fell in love with him. He's a very good player. That's why he made the team. The reason why they succeeded is obvious. They worked really hard. Give me one good reason why I should stay.

Noun

asked the whys behind the surprising decision how one decides that a certain he or she is “the one” is one of the great whys of life

Interjection

why, what a strange thing to say!
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Recent Examples on the Web: Adverb

Here’s a few reasons why Lyft’s decision is the right one. Theodore Schleifer, Recode, "Why Lyft had to beat Uber to an IPO filing," 6 Dec. 2018 One mystery is why the Trump Justice Department defended such an expansive interpretation of the law. The Editorial Board, WSJ, "Endangered Species Habitat Check," 27 Nov. 2018 One reason why bites are rare is that most spiders use their venom exclusively or nearly exclusively on prey rather than for defense. Rob Dunn, Discover Magazine, "Our Attempts to Eradicate Insects are Just Making them Resistant to Pesticides," 16 Nov. 2018 Below, some of the candidates who have taken their families on the road explain why the mom vote is so important. Marisa Lascala, Good Housekeeping, "These 10 Moms Running for Office Need You to Vote on November 6," 30 Oct. 2018 The slow speed would explain why the youngsters were able to watch it for twenty minutes. Kyle Mizokami, Popular Mechanics, "Mystery Submarine Spotted in Swedish Waters," 29 Oct. 2018 At the same time, though, suppliers such as the U.S. and Australia have boosted production and export capabilities—which helps explain why prices remain well below the highs of earlier this decade. Kevin Kingsbury, WSJ, "Natural High: Gas Sellers Spared From China’s Market Slump," 22 Nov. 2018 That’s why scientists will spend a few weeks to find the best spots to deploy these instruments, using InSight’s cameras. Loren Grush, The Verge, "NASA’s InSight lander has just six and a half minutes to land on Mars in one piece," 21 Nov. 2018 Critics, too, question why these ambitious rebuilding plans don’t include new runway space. Barbara Peterson, Condé Nast Traveler, "New York's Airports Are Getting Billion-Dollar Makeovers—But What Will They Actually Change?," 21 Nov. 2018

Recent Examples on the Web: Noun

And the why is that it’s, unfortunately, human nature that has presented itself in so many, many ways. Howard Reich, chicagotribune.com, "Precious possessions: The genocide survivors who kept them tell their stories," 13 July 2018 Businesses and individuals are expected to operate within this principle - why shouldn’t government as well? Jason Lewis, BostonGlobe.com, "Should the Legislature revive the push for a millionaires tax?," 5 July 2018 Makes perfect sense in a why-has-no-one-ever-thought-of-that-before way, no? Lauren Valenti, Marie Claire, "Meet Your Next K-Beauty Obsession: Cushion Eyeliner," 2 Oct. 2015 For many in Westbury, not knowing the how or the why of this homicide case haunts them. CBS News, "Police probe killing of Binghamton University nursing student," 12 Mar. 2018 The following story, about the how and the why, was pieced together using Austin’s own words. Keith Bierygolick, Cincinnati.com, "A school shooter, in his own words: 'I wasn't wanted by anyone'," 23 Feb. 2018 Once the why-does-this-take-so-long process of deboarding finishes, the NAU contingent wanders from A to B (gates) of Terminal 4. Joel Odom, OregonLive.com, "Portland State Vikings complete comeback, top Idaho State," 19 Jan. 2018 But the why of space in its economic context is just as important—maybe even more so. Ed Finn, Slate Magazine, "Space Is Not a Void," 14 Dec. 2017 Where are the lengthy, the tedious, the why-is-this taking-so-long flights? Devon Ivie, CNT, "The Shortest Flight in the U.S. Lasts Just 16 Minutes," 27 Sep. 2017

Recent Examples on the Web: Interjection

And why, oh why, can’t this administration get anything, even a pair of shoes, right? Lynn Yaeger, Vogue, "Melania Trump’s Hurricane Stilettos, and the White House’s Continual Failure to Understand Optics," 29 Aug. 2017 And why, oh why, did my friend have to play back-alley obstetrician? Shannon Boodram, Cosmopolitan, "Read the Fictional Orgasm Essay Jane Wrote on The Bold Type," 3 Aug. 2017 Then why, oh why, make the misguided choice of inviting a political propagandist whose rantings are regularly available on radio, YouTube and any dark den of far-right Internet conspiracy? Lorraine Ali, latimes.com, "The uproar over the Megyn Kelly interview with Alex Jones shows her, and NBC's, lack of news judgment," 12 June 2017 Why, oh why, do the Rangers keep throwing away almost certain victories in the final minutes of playoff games? Filip Bondy, New York Times, "Trying to Prevent a Third Loss, Rangers Embrace Second-Guessing," 30 Apr. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'why.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of why

Adverb

before the 12th century, in the meaning defined above

Conjunction

before the 12th century, in the meaning defined at sense 1

Noun

13th century, in the meaning defined at sense 1

Interjection

1519, in the meaning defined above

History and Etymology for why

Adverb

Middle English, from Old English hwȳ, instrumental case of hwæt what — more at what

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Learn More about why

Dictionary Entries near why

whup

whurl

whvs

why

why bother

whydah

whydunit

Statistics for why

Last Updated

9 Dec 2018

Look-up Popularity

Time Traveler for why

The first known use of why was before the 12th century

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More Definitions for why

why

adverb

English Language Learners Definition of why

 (Entry 1 of 3)

: for what reason or purpose

—used to offer a suggestion or to say that a course of action is not necessary

—used to express irritation or annoyance

English Language Learners Definition of why (Entry 2 of 3)

: the cause, reason, or purpose for which

: for which

English Language Learners Definition of why (Entry 3 of 3)

—used at the beginning of a statement especially to express surprise

why

adverb
\ˈhwī, ˈwī\

Kids Definition of why

 (Entry 1 of 3)

: for what cause or reason Why did you do it?

Kids Definition of why (Entry 2 of 3)

1 : the cause or reason for which We know why you did it.

2 : for which Here's the reason why I did it.

Kids Definition of why (Entry 3 of 3)

used to express surprise, uncertainty, approval, disapproval, or impatience Why, how did you know that?

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More from Merriam-Webster on why

Rhyming Dictionary: Words that rhyme with why

Thesaurus: All synonyms and antonyms for why

Spanish Central: Translation of why

Nglish: Translation of why for Spanish Speakers

Britannica English: Translation of why for Arabic Speakers

Comments on why

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