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

Upon entering the dwelling, guests are greeted with classic Hamptons charm and modern luxury, offering vaulted ceilings, five fireplaces, a sunken living room, formal dining room, and an expansive chef’s kitchen designed for entertaining.

From MarketWatch • Jun. 23, 2026

Upon her retirement in 2024, Simpson and her husband, Jason, spent a year traveling in their 23-foot Winnebago Ekko motorhome and running with community members at events across the country.

From Los Angeles Times • Jun. 17, 2026

Upon his return, he transformed the Tocorón Prison in the northern Venezuelan state of Aragua into a leisure complex, complete with zoo, restaurants, nightclub, betting shop and swimming pool.

From BBC • Jun. 13, 2026

Upon the exit of selling your brand, is where you gain real wealth.

From The Wall Street Journal • Jun. 10, 2026

Upon further study, she thought her handiwork rather dazzling.

From "In the Year of the Boar and Jackie Robinson" by Bette Bao Lord