What is the meaning of come on?

verb

• Appear or become visible; make a showing.
  • usage: "She turned up at the funeral"; "I hope the list key is going to surface again"
  • synonyms: come out, turn up, surface, show up
• Move towards.
  • usage: "We were approaching our destination"; "They are drawing near"; "The enemy army came nearer and nearer"
  • synonyms: approach, near, go up, draw near, draw close, come near
• Develop in a positive way.
  • usage: "He progressed well in school"; "My plants are coming along"; "Plans are shaping up"
  • synonyms: progress, come along, advance, get on, get along, shape up
• Start running, functioning, or operating.
  • usage: "the lights went on"; "the computer came up"
  • synonyms: go on, come up
• Occur or become available.
  • usage: "water or electricity came on again after the earthquake"