Definition of "on" [on]

• Used to indicate position above and supported by or in contact with: The vase is on the table. We rested on our hands and knees. (preposition)
• Used to indicate contact with or extent over (a surface) regardless of position: a picture on the wall; a rash on my back. (preposition)
• Used to indicate location at or along: the pasture on the south side of the river; a house on the highway. (preposition)
• Used to indicate proximity: a town on the border. (preposition)
• Used to indicate attachment to or suspension from: beads on a string. (preposition)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "It was different that night, not the way they yelled at me when I walked into the house with mud on my shoes; more the sound of screeching brakes when my dog was run over - going on and on  forever."
• "• If you're traveling on one of BA's code-sharing and/or marketing partners, such as fellow oneworld alliance member American Airlines, check that carrier's information on  rebookings and refunds."
• "For more on protecting your ears, read our Safety blog on how hearing damage adds up, find out if noise canceling headphones might help, and watch our video (above)  on how to reduce your risk of hearing loss."