Definitions of on:

  • adjective:   in operation or operational
    Example: "Left the oven on"
  • adjective:   (of events) planned or scheduled
    Example: "The picnic is on, rain or shine"
  • adverb:   indicates continuity or persistence or concentration
    Example: "His spirit lives on"
  • adverb:   in a state required for something to function or be effective
    Example: "Turn the lights on"
  • adverb:   with a forward motion
    Example: "We drove along admiring the view"
  • name:  A surname (very rare: popularity rank in the U.S.: #28542)