why

[ wahy, hwahy ]

adverb

1. for what? for what reason, cause, or purpose?:

   Why did you behave so badly?

conjunction

1. for what cause or reason:

   I don't know why he is leaving.

2. for which; on account of which (usually after reason to introduce a relative clause):

   the reason why he refused to go.

3. the reason for which:

   That is why he returned.

noun

, plural whys.

1. a question concerning the cause or reason for which something is done, achieved, etc.:

   a child's unending hows and whys.

2. the cause or reason:

   the whys and wherefores of a troublesome situation.

interjection

1. (used as an expression of surprise, hesitation, etc., or sometimes a mere expletive):

   Why, it's all gone!

why

/ waɪ /

adverb

1. 1. for what reason, purpose, or cause?

      why are you here?

   2. ( used in indirect questions )

      tell me why you're here

pronoun

1. for or because of which

   there is no reason why he shouldn't come

noun

1. usually plural the reason, purpose, or cause of something (esp in the phrase the whys and wherefores )

interjection

1. an introductory expression of surprise, disagreement, indignation, etc

   why, don't be silly!

Usage Note

See reason.

Word History and Origins

Origin of why¹

First recorded before 900; Middle English; Old English hwī, hwȳ, instrumental case of hwæt what; cognate with Old Norse hvī

Word History and Origins

Origin of why¹

Old English hwī; related to Old Norse hvī, Gothic hveileiks what kind of, Latin quī

Example Sentences

Njoku said the next step for abortion funds in the wake of the Amendment 4 results is to gain more support for the next time a similar vote comes up, and that requires a deeper understanding of why some voters cast ballots for Trump as president and in favor of Amendment 4.

From Salon

There’s the question of why exactly Trump’s advisers think he should ask Congress for up to $50 million in taxpayer revenues to fund this thing.

From Slate

They said he had initially been asked his views in a private meeting of Labour MPs, but once that leaked, he felt it necessary to explain publicly why he had come to his opinion.

From BBC

"The impact on trade seems to be more in goods than services... But it underlines why we must be alert to and welcome opportunities to rebuild relations while respecting the decision of the British people."

From BBC

In a world of constraints and an environment under stress, why should he have to share with them?

From Salon