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Upon vs Once - What's the difference?

upon | once |

As adverbs the difference between upon and once

is that upon is being the target of an action while once is one and only one time.

As a preposition upon

is being above and in contact with another.

As a conjunction once is

as soon as; when; after.

upon

English

Alternative forms

* vpon (obsolete)

Preposition

(English prepositions)
  • Being above and in contact with another.
  • :
  • *{{quote-book, year=1899, author=(Hughes Mearns)
  • , title= , passage=Yesterday, upon the stair / I met a man who wasn’t there / He wasn’t there again today / I wish, I wish he’d go away …}}
  • Being directly supported by another.
  • :
  • :
  • Being followed by another so as to form a series.
  • :
  • At a prescribed point in time.
  • :
  • .
  • *
  • , title=(The Celebrity), chapter=5 , passage=Although the Celebrity was almost impervious to sarcasm, he was now beginning to exhibit visible signs of uneasiness, the consciousness dawning upon him that his eccentricity was not receiving the ovation it merited.}}
  • *
  • *:Little disappointed, then, she turned attention to "Chat of the Social World," gossip which exercised potent fascination upon the girl's intelligence.
  • Usage notes

    A somewhat elevated word; the simpler, more general term on is generally interchangeable, and more common in casual American speech. In poetic or legal contexts, upon is common.

    Synonyms

    * (all senses) on * (time) at

    Adverb

    (-)
  • Being the target of an action.
  • He was set upon by the agitated dogs
  • Incidental to a specified point in time or order of action; usually combined with here-, there- or where-.
  • The clock struck noon, whereupon the students proceeded to lunch.

    Derived terms

    * hereupon * thereupon * whereupon

    Statistics

    *

    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

    *