airbubble
nounUK /ˈeəˌbʌb.əl/
US /ˈerˌbʌb.əl/
A small ball of air inside water or another liquid.
The fish blew an air bubble that floated up to the top of the tank.
OTHER MEANINGS
2. A pocket of air trapped inside a solid material such as glass or plastic.
The glass paperweight had a tiny air bubble trapped near its center.
3. A small enclosed space of air in a soapy film or foam.
She laughed as an air bubble popped on her soapy hands.
4. A bubble of air in a liquid that can affect how a machine works.
The mechanic bled the air bubble out of the brake line.