Definition of 'when'
1. adverb
2. conjunction
If something happens when something else is happening, the two things are happening at the same time.
3. conjunction
4. conjunction
You use when to introduce a clause where you mention the circumstances under which the event in the main clause happened or will happen.
5. conjunction
You use when after certain words, especially verbs and adjectives, to introduce a clause where you mention the time at which something happens.
6. pronoun
7. conjunction
8. conjunction
You use when in order to introduce a fact or comment which makes the other part of the sentence rather surprising or unlikely.
COBUILD Advanced English Dictionary. Copyright © HarperCollins Publishers
English Easy Learning GrammarAdverbs and adverbialsWhen you want to add information about how, when, where, or to what extent somethinghas happened, you can use an adverbial. Many adverbials are members ... Read more
English Easy Learning GrammarSubordinationWhen two or more clauses are joined by a conjunction other than and, but, or, or yet,one of the clauses is the main clause; the other clauses are subordinate ... Read more
English Easy Learning GrammarThe interrogativeThe interrogative is normal for many questions. It contains a verb phrase that isfollowed by a subject.
There are two main types of question: those that ... Read more
There are two main types of question: those that ... Read more
Video: pronunciation ofwhen
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Word Frequency
when in British English
adverb
1.
a.
at what time? over what period?
when is he due?
2. say when
3. (subordinating)
at a time at which; at the time at which; just as; after
I found it easily when I started to look seriously
4.
although
he drives when he might walk
6.
at which (time); over which (period)
an age when men were men
noun
▶ USAGE When should not be used loosely as a substitute for in which after a noun which does not refer to a period of time: paralysis is a condition in which (not when) parts of the body cannot be movedCollins English Dictionary. Copyright © HarperCollins Publishers
Word origin
Old English hwanne, hwænne; related to Old High German hwanne, hwenne, Latin cumWord Frequency
when in American English
adverb
1.
a.
at what time?
when did they leave? he asked when he should go
c.
at what point?
when shall I stop pouring?
conjunction
3.
a.
at what time or point
they told us when to eat
b.
at the time that
when we were at college
4.
at which
a time when people must speak out
6.
at whatever time; whenever
she smiles when you praise her
8.
if; considering the fact that
how can he help when they won't let him?
pronoun
9.
what time
until when will you stay?
10.
which time
we came a week ago, since when we've been very busy
noun
Webster’s New World College Dictionary, 4th Edition. Copyright © 2010 byHoughton Mifflin Harcourt. All rights reserved.
Word Frequency
when in American English
(hwen, wen, unstressed hwən, wən)
adverb
1.
at what time or period? how long ago? how soon?
When are they to arrive?
When did the Roman Empire exist?
2.
under what circumstances? upon what occasion?
When is a letter of condolence in order?
When did you ever see such a crowd?
conjunction
3.
at what time
to know when to be silent
4.
at the time or in the event that
when we were young
when the noise stops
5.
at any time; whenever
He is impatient when he is kept waiting
6.
upon or after which; and then
We had just fallen asleep when the bell rang
7.
while on the contrary; considering that; whereas
Why are you here when you should be in school?
pronoun
8.
what time
Till when is the store open?
9.
which time
They left on Monday, since when we have heard nothing
noun
10.
the time of anything
the when and the where of an act
Most material © 2005, 1997, 1991 by Penguin Random House LLC. Modified entries © 2019by Penguin Random House LLC and HarperCollins Publishers Ltd
Word origin
[bef. 1000; ME when(ne), OE hwenne; c. G wann when, wenn if, when (cf. Goth hwan when, how); akin to who, what]Examples of 'when' in a sentencewhen
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Trends ofwhen
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In other languageswhen
British English: when /wɛn/ ADVERB
You use when to ask what time something happened or will happen.
When are you leaving?
- American English: when
- Arabic: مَتَى
- Brazilian Portuguese: quando
- Chinese: 什么时候
- Croatian: kada
- Czech: kdy
- Danish: hvornår
- Dutch: wanneer
- European Spanish: cuándo
- Finnish: milloin
- French: quand
- German: wann
- Greek: πότε
- Italian: quando
- Japanese: いつ
- Korean: 언제
- Norwegian: når
- Polish: kiedy
- European Portuguese: quando
- Romanian: când
- Russian: когда
- Latin American Spanish: cuándo
- Swedish: när
- Thai: เมื่อใด เวลาใด
- Turkish: ne zaman ki
- Ukrainian: коли
- Vietnamese: khi nào
British English: when /wɛn/ CONJUNCTION
You use when to talk about the time at which something happens.
I asked him when he'd be back.
- American English: when
- Arabic: عَنْدَما
- Brazilian Portuguese: quando
- Chinese: 在...的时候
- Croatian: kada
- Czech: když
- Danish: når
- Dutch: wanneer
- European Spanish: cuando
- Finnish: kun
- French: quand
- German: wenn
- Greek: όταν
- Italian: quando
- Japanese: ・・・する時は
- Korean: ...인 때
- Norwegian: når
- Polish: kiedy
- European Portuguese: quando
- Romanian: când
- Russian: когда
- Latin American Spanish: cuando
- Swedish: då
- Thai: เมื่อหรือขณะที่
- Turkish: ne zaman
- Ukrainian: коли
- Vietnamese: khi
Source
Definition of when from theCollins English Dictionary
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