up·on 
/əˈpɑ:n/ preposition
/əˈpɑ:n/ preposition formal 1 : on
▪ He carefully placed the vase upon the table. ▪ They built their city upon a cliff overlooking the sea. ▪ She was seated upon a throne. ▪ an assault upon traditional values ▪ She was admitted to his office immediately upon her arrival. ▪ That kind of behavior is frowned upon. 2 — used to say that someone or something is very close or has arrived ▪ The enemy was suddenly upon us. ▪ The holidays are nearly upon us. [=the holidays are nearly here; the holidays have nearly begun] ▪ Before we knew it, the date of the wedding was upon us. 3 — used to emphasize something that is repeated many times ▪ We removed layer upon layer [=many layers] of old paint from the paneling. ▪ She studied for hour upon hour. [=for many hours] ▪ thousands upon thousands of people
▪ He carefully placed the vase upon the table. ▪ They built their city upon a cliff overlooking the sea. ▪ She was seated upon a throne. ▪ an assault upon traditional values ▪ She was admitted to his office immediately upon her arrival. ▪ That kind of behavior is frowned upon.
