What is the meaning of bubble?

noun

• A hollow globule of gas (e. G., air or carbon dioxide. )
• A speculative scheme that depends on unstable factors that the planner cannot control.
  • usage: "his proposal was nothing but a house of cards"; "a real estate bubble"
  • synonyms: house of cards
• An impracticable and illusory idea.
  • usage: "he didn't want to burst the newcomer's bubble"
• A dome-shaped covering made of transparent glass or plastic.

verb

• Form, produce, or emit bubbles.
  • usage: "The soup was bubbling"
• Flow in an irregular current with a bubbling noise.
  • usage: "babbling brooks"
  • synonyms: ripple, babble, guggle, burble, gurgle
• Rise in bubbles or as if in bubbles.
  • usage: "bubble to the surface"
• Cause to form bubbles.
  • usage: "bubble gas through a liquid"
• Expel gas from the stomach.
  • usage: "In China it is polite to burp at the table"
  • synonyms: burp, belch, eruct