1. To bring to, or maintain at, the boiling point, as of water and other liquids
2. To come to the boiling point and change from a liquid to vapor
3. To cook in boiling liquid

To form produce, or emit bubbles, as of liquids or gases.

To cause to undergo fermentation.

1. To be in an agitated emotional state.
2. To boil vigorously; SYN. roll.
3. To foam as if boiling; SYN. foam.
4. To have violent emotions, such as anger or frustration; SYN. boil.

To boil slowly at low temperature