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Synonyms

if

1 American  
[if] / ɪf /

conjunction

  1. in case that; granting or supposing that; on condition that.

    Sing if you want to. Stay indoors if it rains. I'll go if you do.

  2. even though.

    an enthusiastic if small audience.

  3. whether.

    He asked if I knew Spanish.

  4. (used to introduce an exclamatory phrase).

    If only Dad could see me now!

  5. when or whenever.

    If it was raining, we had to play inside.


noun

  1. a supposition; uncertain possibility.

    The future is full of ifs.

  2. a condition, requirement, or stipulation.

    There are too many ifs in his agreement.

idioms

  1. ifs, ands, or buts, reservations, restrictions, or excuses.

    I want that job finished today, and no ifs, ands, or buts.

if 2 American  
Or IF
if 1 British  
/ ɪf /

conjunction

  1. in case that, or on condition that

    if you try hard it might work

    if he were poor, would you marry him?

  2. used to introduce an indirect question. In this sense, if approaches the meaning of whether

  3. even though

    an attractive if awkward girl

    1. used to introduce expressions of desire, with only

      if I had only known

    2. used to introduce exclamations of surprise, dismay, etc

      if this doesn't top everything!

  4. as it would be if; as though

    he treats me as if I were junior to him

"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

noun

  1. an uncertainty or doubt

    the big if is whether our plan will work at all

  2. a condition or stipulation

    I won't have any ifs or buts

"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
IF 2 British  

abbreviation

  1. intermediate frequency

"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

if More Idioms  

Usage

If meaning “whether,” as in I haven't decided if I'll go, is sometimes criticized, but the usage is long established as standard.

Related Words

If, provided, providing imply a condition on which something depends. If is general. It may be used to indicate suppositions or hypothetical conditions (often involving doubt or uncertainty): If you like, we can go straight home. If I had known, I wouldn't have gone. If may mean even though: If I am wrong, you are not right. It may mean whenever: If I do not understand, I ask questions. Provided always indicates some stipulation: I will subscribe ten dollars provided ( on the condition ) that you do, too. Provided he goes, we can go along. Providing means the same as provided, that is, just in case some certain thing should happen: We will buy the house, providing ( provided ) we can get a mortgage.

Etymology

Origin of if

First recorded before 900; Middle English, variant of yif, Old English gif, gef; akin to Old Norse ef “if,” Gothic ibai “whether,” Old High German iba “condition, stipulation”

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

It isn’t yet known if he was killed by police fire or took his own life, Smith said.

From The Wall Street Journal • Apr. 20, 2026

So the crickets are actually chirping loudly, if you listen to them.

From Slate • Apr. 20, 2026

Powell has said he’ll stay on as “chair pro tem” if Warsh isn’t confirmed by then.

From MarketWatch • Apr. 20, 2026

In seeking the injunction, Bonta’s office argues that Amazon threatens “dire consequences if vendors do not comply. Vendors, cowed by Amazon’s overwhelming bargaining leverage and fearing punishment, comply,” according to the filing.

From Los Angeles Times • Apr. 20, 2026

“Not if I have anything to say about it!”

From "Legendary Frybread Drive-In" by Cynthia Leitich Smith