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

Throughout “Those Who Are About to Die,” the reader comes upon fascinating generalizations, usually introduced by attention-arousing brief sentences.

From The Wall Street Journal • Apr. 3, 2026

But worse yet, they said, the outcome “would cast a shadow over the citizenship of millions upon millions of Americans, going back generations.”

From Los Angeles Times • Apr. 1, 2026

He was also convicted of possessing a knife, which police found upon arrest.

From BBC • Mar. 31, 2026

Through a trust, he also indirectly controls voting shares that represent nearly 46 million common shares upon conversion.

From MarketWatch • Mar. 31, 2026

They played with his tail, crawled upon his back, lifted up his lips, and inspected his teeth.

From "Summer of the Monkeys" by Wilson Rawls