First Known Use: before 12th century
Dictionary
1why
adverb \ˈhwī, ˈwī\
: 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
Full Definition of WHY
: for what cause, reason, or purpose <why did you do it?>
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Origin of WHY
Middle English, from Old English hwȳ, instr. case of hwæt what — more at what
2why
conjunction
: the cause, reason, or purpose for which
: for which
Full Definition of WHY
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>
See why defined for English-language learners
First Known Use of WHY
before 12th century
3why
noun
plural whys
Definition of WHY
2
: a baffling problem : enigma
See why defined for English-language learners
First Known Use of WHY
13th century
4why
interjection
—used at the beginning of a statement especially to express surprise
Full Definition of WHY
—used to express mild surprise, hesitation, approval, disapproval, or impatience <why, here's what I was looking for>
See why defined for English-language learners
First Known Use of WHY
1519
WHY Defined for Kids
1why
adverb \ˈhwī, ˈwī\
Definition of WHY for Kids
: for what cause or reason <Why did you do it?>
2why
conjunction
Definition of WHY for Kids
1
: the cause or reason for which <We know why you did it.>
2
: for which <Here's the reason why I did it.>
3why
interjection
Definition of WHY for Kids
—used to express surprise, uncertainty, approval, disapproval, or impatience <Why, how did you know that?>
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