upon

American  

[uh-pon, uh-pawn] / əˈpɒn, əˈpɔn /

preposition

1. up and on; upward so as to get or be on.

   He climbed upon his horse and rode off.

2. in an elevated position on.

   There is a television antenna upon every house in the neighborhood.

3. in or into complete or approximate contact with, as an attacker or an important or pressing occasion.

   The enemy was upon us and our soldiers had little time to escape. The Christmas holiday will soon be upon us and we have hardly begun to buy gifts. The time to take action is upon us.

4. immediately or very soon after.

   She went into mourning upon her husband's death.

5. on the occasion of.

   She was joyful upon seeing her child take his first steps.

6. on (in any of various senses, used as an equivalent of on with no added idea of ascent or elevation, and preferred in certain cases only for euphonic or metrical reasons).

   He swore upon his honor as a gentleman.

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upon British  

/ əˈpɒn /

preposition

1. another word for on

2. indicating a position reached by going up

   climb upon my knee

3. imminent for

   the weekend was upon us again

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upon Idioms  

1. see act on (upon); call on (upon); chance on (upon); come across (upon); come on (upon); count on (upon); dawn on (upon); dwell on (upon); enter on (upon); fall back on (upon); fall on (upon); grow on (upon); hard on (upon); hit on (upon); incumbent upon; light on (upon); once upon a time; pitch on (upon); play on (upon); put upon; seize on (upon); set at (upon); take it upon oneself; wait on (upon); weigh on (upon); work on (upon).

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Etymology

Origin of upon

First recorded in 1150–1200; Middle English; up (adverb) + on (preposition)

Example Sentences

This was certainly reinforced by the universal condemnation heaped upon then-Rep.

From The Wall Street Journal • Jun. 8, 2026

Once upon a time, a dynamic young entrepreneur came to him with a brilliant idea that, on paper, could revolutionize healthcare diagnoses and reduce costs exponentially.

From MarketWatch • Jun. 8, 2026

This material is based upon work supported by the U.S.

From Science Daily • Jun. 6, 2026

We learn how Iceland’s glaciers, essentially rivers of varying pace, begat their unique ecosystems, but also how they provided the breathtaking terrain upon which Magnason’s grandparents Hulda and Árni fell in love.

From Los Angeles Times • Jun. 5, 2026

Perched upon a wide oak table, among more strange items, Duane spied a snowy owl reading from a large open book.

From "The Very, Very Far North" by Dan Bar-el