1. (noun)bubble a hollow globule of gas (e.g., air or carbon dioxide) Synonyms: house of cards
2. (noun)house of cards, bubble a speculative scheme that depends on unstable factors that the planner cannot control Synonyms: bubble, house of cards, card-house, cardhouse, cardcastle
3. (noun)bubble an impracticable and illusory idea Synonyms: house of cards
4. (verb)bubble a dome-shaped covering made of transparent glass or plastic Synonyms: house of cards