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Synonyms

once

American  
[wuhns] / wʌns /

adverb

  1. at one time in the past; formerly.

    I was a farmer once;

    a once powerful nation.

  2. a single time: We go to a movie once a week.

    We ate there just once.

    We go to a movie once a week.

  3. even a single time; at any time; ever.

    If the facts once become known, it will be just too bad.

  4. by a single step, degree, or grade.

    a cousin once removed.


adjective

  1. former; having at one time been.

    the once and future king.

conjunction

  1. if or when at any time; if ever.

  2. whenever; as soon as.

    Once you're finished, you can leave.

noun

  1. a single occasion; one time only.

    Once is enough.

idioms

  1. once and again, repeatedly.

    He has been told once and again not to slam the door.

  2. all at once,

    1. simultaneously.

      The children were running, screaming, and throwing things all at once.

    2. suddenly.

      All at once the rain came down.

  3. at once,

    1. at the same time; simultaneously.

      Don't all speak at once.

    2. immediately; promptly.

      Tell him to come at once!

  4. once upon a time, at some unspecified past time, especially a long time ago.

    Once upon a time, in a faraway land, there lived a prince and princess.

  5. once or twice, a very few times; infrequently.

    I've seen her in the elevator once or twice.

  6. once and for all, decisively; finally: Also once for all.

    Let's settle this problem once and for all.

  7. once in a while, at intervals; occasionally.

    She stops in to see us once in a while.

once British  
/ wʌns /

adverb

  1. one time; on one occasion or in one case

  2. at some past time; formerly

    I could speak French once

  3. by one step or degree (of relationship)

    a cousin once removed

  4. (in conditional clauses, negatives, etc) ever; at all

    if you once forget it

  5. multiplied by one

    1. conclusively

    2. occasionally

  6. conclusively; for the last time

  7. occasionally; now and then

  8. a few times

  9. used to begin fairy tales and children's stories

"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

conjunction

  1. (subordinating) as soon as; if ever or whenever

    once you begin, you'll enjoy it

"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. one occasion or case

    you may do it, this once

    1. suddenly or without warning

    2. simultaneously

    1. immediately

    2. simultaneously

  2. this time, if (or but) at no other time

"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
once More Idioms  

    More idioms and phrases containing once


Etymology

Origin of once

First recorded before 1150; Middle English ones, Old English ānes, originally genitive of ān “one” replacing Middle English enes, Old English ǣnes “once,” equivalent to ǣne “once” (originally instrumental of ān ) + -es adverb suffix; one, -s 1

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.

In my experience, once you get past the now obligatory bot, getting in touch with an agent was quite fast — under five minutes.

From Salon

Young tech companies once might have complemented lower salaries with generous equity packages.

From The Wall Street Journal

Even leaders who were once considered among the U.S. president’s closest allies have expressed growing frustration with him over the Iran conflict and his demands.

From The Wall Street Journal

But while that once meant sizing up a candidate’s experience and credentials against the going market rate, it increasingly means feeding the candidate’s personal data into an algorithm.

From MarketWatch

These flows are nonspecific, meaning they can carry many types of proteins at once.

From Science Daily