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Once vs If - What's the difference?

once | if |

As conjunctions the difference between once and if

is that once is as soon as; when; after while if is supposing that, assuming that, in the circumstances that; used to introduce a condition or choice.

As an adverb once

is one and only one time.

As a noun if is

an uncertainty, possibility, condition, doubt etc.

As an initialism IF is

interactive fiction.

once

English

(wikipedia once)

Adverb

(-)
  • (lb) One and only one time.
  • :
  • (lb) Formerly; during some period in the past.
  • :
  • *
  • *:Orion hit a rabbit once ; but though sore wounded it got to the bury, and, struggling in, the arrow caught the side of the hole and was drawn out. Indeed, a nail filed sharp is not of much avail as an arrowhead; you must have it barbed, and that was a little beyond our skill. Ikey the blacksmith had forged us a spearhead after a sketch from a picture of a Greek warrior; and a rake-handle served as a shaft.
  • *{{quote-book, year=1944, author=(w)
  • , title= The Three Corpse Trick, chapter=5 , passage=The hovel stood in the centre of what had once been a vegetable garden, but was now a patch of rank weeds. Surrounding this, almost like a zareba, was an irregular ring of gorse and brambles, an unclaimed vestige of the original common.}}
  • *{{quote-magazine, date=2013-06-14, author=(Jonathan Freedland)
  • , volume=189, issue=1, page=18, magazine=(The Guardian Weekly) , title= Obama's once hip brand is now tainted , passage=Now we are liberal with our innermost secrets, spraying them into the public ether with a generosity our forebears could not have imagined. Where we once sent love letters in a sealed envelope, or stuck photographs of our children in a family album, now such private material is despatched to servers and clouds operated by people we don't know and will never meet.}}
  • (lb) Multiplied by one: indicating that a number is multiplied by one.
  • :
  • As soon as.
  • *{{quote-magazine, date=2013-06-07, author= Ed Pilkington
  • , volume=188, issue=26, page=6, magazine=(The Guardian Weekly) , title= ‘Killer robots’ should be banned in advance, UN told , passage=In his submission to the UN, [Christof] Heyns points to the experience of drones. Unmanned aerial vehicles were intended initially only for surveillance, and their use for offensive purposes was prohibited, yet once strategists realised their perceived advantages as a means of carrying out targeted killings, all objections were swept out of the way.}}

    Coordinate terms

    * (one time) twice, thrice, often, never, seldom * (formerly) yesterday, tomorrow

    See also

    * once again, once more * once and for all * once in a blue moon * once in a while * once removed * once upon a time

    Conjunction

    (English Conjunctions)
  • As soon as; when; after.
  • We'll get a move on once we find the damn car keys!
    Once you have obtained the elven bow, return to the troll bridge and trade it for the sleeping potion.
    Once he is married, he will be able to claim the inheritance.
  • * {{quote-news, year=2011
  • , date=September 27 , author=Alistair Magowan , title=Bayern Munich 2 - 0 Man City , work=BBC Sport citation , page= , passage=Not only were Jupp Heynckes' team pacey in attack but they were relentless in their pursuit of the ball once they had lost it, and as the game wore on they merely increased their dominance as City wilted in the Allianz Arena.}}

    Statistics

    *

    if

    English

    (wikipedia if)

    Conjunction

    (English Conjunctions)
  • Supposing that, assuming that, in the circumstances that;
  • If it rains, I will get wet .
  • Supposing that;
  • I'd prefer it if you took your shoes off.
  • Although;
  • He was a great friend, if a little stingy at the bar.
  • (computing) In the event that a statement is true (a programming statement that acts in a similar manner).
  • If A, then B, else C.
  • Whether;
  • I don't know if I want to go or not.
  • * 1715–1717 , , Alma; or, The Progress of the Mind , Canto III:
  • Quoth Matthew, “”
  • (usually hyperbolic) Even if; even in the circumstances that.
  • * 2004', (singers), “'''If It’s The Last Thing I Do” (song), in ''You Do Your Thing (album):
  • If' it’s the last thing I do / '''If''' it takes me from Tubilo to Timbuktu / '''If''' it’s the last thing I do / I’m gonna dodge every road block, speed trap, county cop / To get my hands on you / ' If it’s the last thing I do.

    Usage notes

    * Specifically a subordinating conjunction.

    Derived terms

    * iff * if and only if * if clause * if only * as if * even if * if so be

    Alternative forms

    * ifen * iffen

    Noun

    (en noun)
  • (informal) An uncertainty, possibility, condition, doubt etc.
  • * 1709, Susannah Centlivre, The Busy Body'', Act III, in John Bell (ed.), ''British Theater , J. Bell (1791), page 59,
  • Sir Fran.'' Nay, but Chargy, if——— ¶ ''Miran.'' Nay, Gardy, no Ifs'''.——Have I refus'd three northern lords, two British peers, and half a score knights, to have put in your ' Ifs ?
  • * 1791 January, "Richard?on’s Chemical Principles of the Metallic Arts''", in ''The Monthly Review , R. Griffiths, page 176,
  • Well might Bergman add, (in his Sciographia,''), if the compari?on that has been made, &c. be ju?t.” The pre?ent writer makes no ''ifs about the matter, and has ?uperadded a little inaccuracy of his own, […]
  • * {{quote-news, year=2013, date=April 9, author=Andrei Lankov, title=Stay Cool. Call North Korea’s Bluff., work=New York Times citation
  • , passage=Even if they managed to strike Japan, the United States or South Korea with nuclear weapons — a big if , given that they do not have a reliable delivery system — they could not save themselves from ultimate defeat.}}

    Derived terms

    * big if *

    See also

    * and * else * false * or * then * true

    Statistics

    *