Etymology From Middle English if, yif, yef, from Old English ġif (“if”), from Proto-West Germanic *jabu, *jabē, from Proto-Germanic *jabai (“when, if”). Cognate with Scots gif (“if, whether”), Saterland Frisian af, of (“if, whether”), West Frisian oft (“whether”), Dutch of (“or, whether, but”), Middle Low German ef, if, af, of ("if; whether"; > German Low German of), German ob (“if, whether”), Icelandic ef (“if”).
Supposing that, assuming that, in the circumstances that; used to introduce a condition that may be (or prove to be) either true or false.
If crossing the road, make sure you look both ways.
If I give you the money would/will you buy it for me?
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If you prefer, I can come tomorrow instead.
I'll, if I have time, do it next week.
I'll come only if you will do the driving.
Fetch me a cold beer if there's one in the fridge.
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Computing, Engineering, Mathematics, Natural sciences, Physical sciences, Sciences A keyword that invokes conditional processing: in the event that a given condition is true, execute the given statement(s) (otherwise execute other statements).
if A then B else C
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Supposing that; used with past or past perfect subjunctive to indicate a counterfactual or hypothetical condition.
If she hadn't told me, I wouldn't know.
"You would be healthier if you would give up smoking" "Well, if I were rich, I'd go to one of those hypnosis therapies to quit".
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She could have used my car if the battery wasn't flat.
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Excessive, Usually Even if; even in the circumstances that.
I wouldn't marry you if you were the last man on earth.
You're finishing your chowder if you sit there all afernoon!
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“Wait a minute!” said the girl: “I wouldn’t hurry by, if it was you that was coming out to be hung, the next time eight o’clock struck, Bill. I’d walk round and round the place till I dropped, if the snow was on the ground, and I hadn’t a shawl to cover me.”1838, Boz [pseudonym; Charles Dickens], Oliver Twist; […], volume (please specify |volume=I, II, or III), London: Richard Bentley, […], →OCLC:
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.2004, David Lee Murphy and Kim Tribble (writers), Montgomery Gentry (singers), “If It’s The Last Thing I Do” (song), in You Do Your Thing (album)
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Considering the fact that; given that; introducing a condition that is known to be true.
The drain's blocked — and if the drain's blocked, the water won't flow.
O what of Gods then boots it to be borne, / If old Aveugles ſonnes ſo euill heare?1596, Edmund Spenser, “Book I”, in The Faerie Queene. […], part I (books I–III), London: […] [Richard Field] for William Ponsonbie, →OCLC, stanza ii, page 66:
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When; whenever; every time that.
If you heat water to 100° C, it boils.
If it rains, it pours.
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Although; used to introduce a concession; may..but.
He was a great friend, if a little stingy at the bar.
She won her team's admiration, if not the award, for her performance.
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Both Spear & Davis were indicted in the witchhunt surrounding the sensational (if nonexistent) "Revere sex ring."1981 April 11, Mitzel, “Kopacz Acquitted In Barbre Killing”, in Gay Community News, page 1:
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Proscribed, Sometimes Whether; used to introduce a noun clause, an indirect question, that functions as the direct object of certain verbs.
I don't know if I want to go or not.
Quoth Matthew, “ […] / She doubts if two and two make four, / […] ”1715–1717, Matthew Prior, Alma; or, The Progress of the Mind, Canto III
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It is doubtful if the Victorian Londoner needed any warning, for the artful mobsmen, toolers, whizzers and dippers, together with their stickman accomplices, were everywhere in the crowds, in the underground, on railway trains […]1976, Michael Harrison, Beyond Baker Street: A Sherlockian Anthology, page 117:
If his Russian was music, his English was murder.1957 March 7, Vladimir Nabokov, chapter 3.3, in Pnin, Heinemann, page 66:
If the outcome of the land war on the Eastern Front is usually seen as decisive, historical views on the importance of the air war are mixed.2015, Phillips Payson O'Brien, How the War was Won: Air-Sea Power and Allied Victory in World War II, page 8:
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If the Russians out-produced the Japanese in individual units, the Japanese out-produced the USSR in terms of technological quality.2015, Phillips Payson O'Brien, How the War was Won: Air-Sea Power and Allied Victory in World War II, page 65:
If the Americans knew how they wanted to use strategic air power but not what to attack, the British had a huge number of plans about what to attack but almost no means to adequately deliver the necessary blow.2015, Phillips Payson O'Brien, How the War was Won: Air-Sea Power and Allied Victory in World War II, page 103:
If the Poles resisted imperial rule, the Ukrainians threatened the unity of the “reunified” Catherinian empire by claiming an identity distinct from the Russian.2023, Serhii Plokhy, The Russo-Ukrainian War: The Return of History, page 17:
If the collapse of the USSR was sudden and largely bloodless, growing strains between its two largest successors would develop into limited fighting in the Donbas in 2014 and then into all-out warfare in 2022, causing death, destruction, and a refugee crisis on a scale not seen in Europe since the Second World War.2023, Serhii Plokhy, The Russo-Ukrainian War: The Return of History, page 1970:
Etymology From Middle English if, yif, yef, from Old English ġif (“if”), from Proto-West Germanic *jabu, *jabē, from Proto-Germanic *jabai (“when, if”). Cognate with Scots gif (“if, whether”), Saterland Frisian af, of (“if, whether”), West Frisian oft (“whether”), Dutch of (“or, whether, but”), Middle Low German ef, if, af, of ("if; whether"; > German Low German of), German ob (“if, whether”), Icelandic ef (“if”).
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Informal An uncertainty, possibility, condition, doubt etc.
The board can't approve this project; there are too many ifs.
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?
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Well might Bergman add, (in his Sciographia,), “if the compariſon that has been made, &c. be juſt.” The preſent writer makes no ifs about the matter, and has ſuperadded a little inaccuracy of his own, […]1791 January, “Richardſon’s Chemical Principles of the Metallic Arts”, in The Monthly Review, R. Griffiths, page 176:
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.2013 April 9, Andrei Lankov, “Stay Cool. Call North Korea’s Bluff.”, in New York Times: