A bubble can represent:
- An enclosed or self-contained environment
- Isolation or ignorance, as in "he's living in a bubble and doesn't know what's going on"
- Protection
- A void or hole, such as an air bubble in Swiss cheese
Bubbles in a liquid can represent:
- Fun or relaxation
- Stimulation
- Lightness or airiness
- A feeling of celebration
Blowing a bubble can represent a process or project. A bubble bursting can represent the end of a process or project, disappointment, or destruction.