bubble

noun

a dome-shaped covering made of transparent glass or plastic
an impracticable and illusory idea
“They didn't want to burst the newcomer's bubble.”
a speculative scheme that depends on unstable factors that the planner cannot control

house of cards
a hollow globule of gas (e.g., air or carbon dioxide)

verb

to expel gas from the stomach
“They were bubbling all night.”
belch
to form, produce, or emit bubbles
“The machine should be bubbling.”
to cause to form bubbles
“I bubble gas through a liquid.”
to rise in bubbles or as if in bubbles
“The diver bubbled to the surface.”
to flow in an irregular current with a bubbling noise
“The creek bubbled through our back yard.”
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