on 1 touching or being supported by a particular surface: The plate's on the table. | You have mud on your shoes. | The answer is written on page 25. 2 hanging from, supported by or connected to a particular thing: Stand on one foot. | pictures stuck on the wall | a ball on a string 3 a) in a particular place, building or area of land: Several bombs landed on the runway. | He grew up on a ranch in California. b) American English in a particular road: We live on Mulberry Drive. | I met Amy on the street the other day. 4 in a particular direction: On my right sat the Chancellor. | As the troops marched on the city, the leaders planned their escape. 5 used to show the person or thing affected by an action or someone's behaviour: a tax on cigarettes | The divorce has had a particularly bad effect on the children. 6 on one of the sides of something such as a river or road: a cafe on the river | a beautiful village on the Austrian border | trees on both sides of the street 7 on Friday/August 2nd/my birthday at some time during a particular day: They arrive on Tuesday. | I was born on July 1st. 8 about a particular subject: a book on India | advice on what to wear 9 in a bus, train, aircraft etc: Everyone on the plane was frightened. | He managed to be on the first train back to London. 10 used to say what food someone needs to survive, what fuel1 (1) something needs to operate etc: We can't live on rice and water forever. | Many cars nowadays run on lead free petrol. 11 used to say what money people use to live, the amounts of money someone earns etc: Some families in the ghettos have been on welfare all their lives. | People on high salaries should pay more tax. 12 informal used to say that someone takes a particular drug or medicine: Since she's been on Prozac she's been a different person. 13 on the radio/telephone using a radio or telephone: Shut up! I'm on the phone. 14 on a trip/journey etc during a trip, journey etc: I met several people on the voyage. | On my way to work the car broke down. 15 used to say what has been used to do something: Phil had torn his shirt on a nail. | It's amazing what you can do on these new word processors. 16 formal immediately after something has happened or after someone has done something : on doing sth: On hearing the news of the air attack most foreigners headed for the border. | on arrival/sb's return etc: On arrival at reception, guests should sign the visitors' book. | on sth: On the general's command, all soldiers must salute. 17 used to say that someone is a member of a team, organization etc: What team did you say your boyfriend was on? 18 compared with another person or thing: This essay is a definite improvement on your last one. | Sales are 10% up on last year. 19 have/carry etc sth on you informal to have a particular thing in your pocket, your bag etc: How much cash do you have on you? 20 spoken used to say that someone will pay for something such as a drink, a meal etc: Drinks are on Harold! 21 informal if a machine stops, breaks etc on you, it stops or breaks while you are using it: Suddenly the telephone went dead on me. home