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RELATED WORDS

albeit, although, at, during, meanwhile, whereas, while, howbeit

Origin of when

before 1000; Middle English when(ne), Old English hwenne; cognate with German wann when, wenn if, when (compare Gothic hwan when, how); akin to who, what
Can be confusedwhen whencewen when

when's

[hwenz, wenz]

contraction of when is: When's the show over?
contraction of when does: When's the next train leave?
contraction of when has: When's he ever been an authority?

Usage note

See contraction.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for when

when

adverb

  1. at what time? over what period?when is he due?
  2. (used in indirect questions)ask him when he's due
say when to state when an action is to be stopped or begun, as when someone is pouring a drink
(subordinating) at a time at which; at the time at which; just as; afterI found it easily when I started to look seriously
althoughhe drives when he might walk
considering the fact thathow did you pass the exam when you'd not worked for it?
at which (time); over which (period)an age when men were men

noun

(usually plural) a question as to the time of some occurrence

Word Origin for when

Old English hwanne, hwænne; related to Old High German hwanne, hwenne, Latin cum

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 moved
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for when
adv.

Old English hwænne, hwenne, hwonne, from Germanic pronomial stem *khwa- (cf. Old Saxon hwan, Old Frisian hwenne, Middle Dutch wan, Old High German hwanne, German wann "when"), from PIE interrogative base *qwo- (see who).

Online Etymology Dictionary, © 2010 Douglas Harper
Idioms and Phrases with when

when

In addition to the idioms beginning with when

  • when all's said and done
  • when in Rome do as the Romans do
  • when it comes to
  • when least expected
  • when one's back is turned
  • when one's ship comes in
  • when pigs fly
  • when the cat's away, the mice will play
  • when the chips are down
  • when the dust has settled
  • when the going gets tough, the tough get going
  • when the shit hits the fan

also see:

  • cross a bridge when one comes to it
  • push comes to shove, when
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.