why

1 of 4

adverb

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

why

2 of 4

conjunction

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

3 of 4

noun

plural whys
1
: reason, cause
wants to know the whys and wherefores
2
: a baffling problem : enigma

why

4 of 4

interjection

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

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!
Recent Examples on the Web
Adverb
So that’s the how and why; the real — unfair — question is whether the song comes close to measuring up to the Beatles or their collective solo works’ towering legacy. Jem Aswad, Variety, 2 Nov. 2023 Several wanted to know why the Chinese airship was allowed to float all the way to the Atlantic Ocean before it was shot down. Ellen Nakashima, Washington Post, 11 Feb. 2023 Police did not say how or why the shooting took place and, as of Friday, no arrests had been made. Natalie Neysa Alund, USA TODAY, 10 Feb. 2023 At a separate Senate subcommittee hearing, lawmakers repeatedly pressed administration officials, including Pentagon military leaders, about why the balloon was not shot down over sparsely populated areas of Alaska. Matthew Lee and Eric Tucker, ajc, 10 Feb. 2023 That continuance prompted Bolden to use profanity on the courthouse steps when speaking at a news conference, and is part of why Griggsby is seeking to hold him in criminal contempt. Lee O. Sanderlin, Baltimore Sun, 10 Feb. 2023 This is also a population-level study, so there is no way to pinpoint exactly why people exposed to these kinds of air pollutions would have a higher risk of depression. Jen Christensen, CNN, 10 Feb. 2023 If your dentist wants to X-ray your teeth, Dr. Hershkowitz recommends asking them why. Drew Schwartz, SELF, 10 Feb. 2023 The notes do not go into detail on why the Archives would have sought the material that was sent to Boston. Colleen Long, BostonGlobe.com, 10 Feb. 2023
Noun
There’s got to be a why. Vulture, 29 Mar. 2023 The show never aims its considerable wit and girl power vibe to get a firm grip on the troubling tributaries that flow just underneath the why-ness of the show: These women, nobility be damned, are one and all inextricably tied to a fundamentally-flawed man. Rod Stafford Hagwood, Sun Sentinel, 12 Oct. 2022 Cain opines on the why-and-how of private mega-yachts, which have grown mind-bogglingly massive (such as the 533-foot-long Eclipse, replete with submarine, owned by Russian business mogul Roman Abramovich). Laura Manske, Forbes, 27 Oct. 2021 Not everyone may want to abandon teaching manners altogether, but these insights do suggest rethinking our approach, focusing as much on the why of courtesy as the how. BostonGlobe.com, 23 Oct. 2019 Worst of all, the cult of lethality attempts to divorce the how of killing from the why, an insane proposition given that military force is deployed in the service of political outcomes. Jared Keller, The New Republic, 9 Sep. 2019 And the why is that it’s, unfortunately, human nature that has presented itself in so many, many ways. Howard Reich, chicagotribune.com, 13 July 2018 History doesn’t often remember the why, just the what. Philip Elliott, Time, 26 Sep. 2017 But instead of getting bogged down by the calories consumed or the grams of fat encountered, Alpert turned the conversation to the why. Logan Sykes, Town & Country, 2 Jan. 2017
Interjection
Why, oh why, do the Rangers keep throwing away almost certain victories in the final minutes of playoff games? Filip Bondy, New York Times, 30 Apr. 2017

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'why.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Adverb

Middle English, from Old English hwȳ, instrumental case of hwæt what — more at what entry 1

First Known Use

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

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

Dictionary Entries Near why

Cite this Entry

“Why.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/why. Accessed 29 Mar. 2024.

Kids Definition

why

1 of 4 adverb
(ˈ)hwī How to pronounce why (audio)
(ˈ)wī
: for what cause or reason
why did you do it

why

2 of 4 conjunction
1
: the cause or reason for which
know why you did it
2
: for which : on account of which
the reason why she did it

why

3 of 4 noun
ˈhwī,
ˈwī
plural whys
: reason entry 1 sense 1a
explained the whys and wherefores of the sudden price increase

why

4 of 4 interjection
(ˌ)wī,
(ˌ)hwī
used to express surprise, indecision, approval, disapproval, or impatience
why, I didn't know that

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