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definitions

what-if

[hwuht-if, hwot‐, wuht‐, wot‐]
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adjective

hypothetical: a what-if scenario.

noun

a hypothetical case or situation; conjecture: a series of what-ifs.

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RELATED WORDS

but, imagine, supposing, that

Nearby words

  1. what's the matter,
  2. what's up,
  3. what's what,
  4. what's with,
  5. what've,
  6. what-you-may-call-it,
  7. whata,
  8. whataboutery,
  9. whataboutism,
  10. whatchamacallit

Origin of what-if

First recorded in 1980–85

what

[hwuht, hwot, wuht, wot; unstressed hwuh t, wuh t]

pronoun

(used interrogatively as a request for specific information): What is the matter?
(used interrogatively to inquire about the character, occupation, etc., of a person): What does he do?
(used interrogatively to inquire as to the origin, identity, etc., of something): What are those birds?
(used interrogatively to inquire as to the worth, usefulness, force, or importance of something): What is wealth without friends?
(used interrogatively to request a repetition of words or information not fully understood, usually used in elliptical constructions): You need what?
(used interrogatively to inquire the reason or purpose of something, usually used in elliptical constructions): What of it?
how much?: What does it cost?
(used relatively to indicate that which): I will send what was promised.
whatever; anything that: Say what you please. Come what may.
the kind of thing or person that: He said what everyone expected he would. They are just what I was expecting.
as much as; as many as: We should each give what we can.
the thing or fact that (used in parenthetic clauses): He went to the meeting and, what was worse, insisted on speaking.
(used to indicate more to follow, additional possibilities, alternatives, etc.): You know what? Shall we go or what?
(used as an intensifier in exclamatory phrases, often followed by an indefinite article): What luck! What an idea!
British. don't you agree?: An unusual chap, what?
Nonstandard. that; which; who: She's the one what told me.

noun

the true nature or identity of something, or the sum of its characteristics: a lecture on the whats and hows of crop rotation.

adjective

(used interrogatively before nouns): What news? What clothes shall I pack?
whatever: Take what supplies you need.

adverb

to what extent or degree? how much?: What does it matter?
(used to introduce a prepositional phrase beginning with with): What with storms and all, their return was delayed.
Obsolete. for what reason or purpose? why?

interjection

(used in exclamatory expressions, often followed by a question): What, no salt?

conjunction

Older Use. as much as; as far as: He helps me what he can.

Origin of what

before 900; Middle English; Old English hwæt; cognate with German was, Dutch wat, Old Norse hvat; akin to Gothic hwa, Latin quod, Greek tí

Usage note

25. See doubt.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for what if

what

determiner

  1. used with a noun in requesting further information about the identity or categorization of somethingwhat job does he do?
  2. (as pronoun)what is her address?
  3. (used in indirect questions)does he know what man did this?; tell me what he said
  1. the (person, thing, persons, or things) thatwe photographed what animals we could see
  2. (as pronoun)bring me what you've written; come what may
(intensifier; used in exclamations)what a good book!

adverb

in what respect? to what degree?what do you care?

pronoun

not standard which, who, or that, when used as relative pronounsthis is the man what I saw in the park yesterday
what about what do you think, know, feel, etc, concerning?
what for
  1. for what purpose? why?
  2. informala punishment or reprimand (esp in the phrase give (a person) what for)
what have you someone, something, or somewhere unknown or unspecifiedcars, motorcycles, or what have you
what if
  1. what would happen if?
  2. what difference would it make if?
what matter what does it matter?
what's what informal the true or real state of affairs

interjection

informal don't you think? don't you agree?splendid party, what?

Word Origin for what

Old English hwæt; related to Old Frisian whet, Old High German hwaz (German was), Old Norse hvatr

usage

The use of are in sentences such as what we need are more doctors is common, although many people think is should be used: what we need is more doctors

what-if

noun

informal a hypothetical question; speculationone of the great what-ifs of modern history
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 what if

what

pron.

Old English hwæt, from Proto-Germanic *khwat (cf. Old Saxon hwat, Old Norse hvat, Danish hvad, Old Frisian hwet, Dutch wat, Old High German hwaz, German was, Gothic hva "what"), from PIE *qwod, neuter singular of *qwos "who" (see who).

Meaning "what did you say?" is recorded from c.1300; as an interrogative expletive at the end of sentences it is first recorded 1785, common early 20c. in affected British speech. Or what as an alternative end to a question is first attested 1766. "To give one what for is to respond to his remonstrant what for? by further assault" [Weekley]. The phrase is attested from 1873. What's-his-name for "unspecified person" is attested from 1690s; variant whatsisface is first recorded 1967. What's up? "what is happening?" first recorded 1881.

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

what if

Suppose that, as in What if the speaker doesn't get here in time? This expression is in effect a shortening of “what would happen if.” It was first recorded about 1420.

what

In addition to the idioms beginning with what

  • what about
  • what do you know
  • what do you take me for?
  • what for
  • what gives
  • what goes around comes around
  • what have you
  • what if
  • what in the world
  • what is more
  • what it takes
  • what makes one tick
  • what of it?
  • what the hell
  • what with

also see:

  • come what may
  • for all one is (what it's) worth
  • get what's coming to one
  • it's (what) a zoo
  • just what the doctor ordered
  • know the score (what's what)
  • left hand doesn't know what the right hand is doing
  • no matter (what)
  • on earth, what
  • or what?
  • practice what you preach
  • sauce for the goose is sauce for the gander, what's
  • so what
  • where's (what's) the beef?
  • you know something (you know what)
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.