| 1. | to change from a liquid to a gaseous state, producing bubbles of gas that rise to the surface of the liquid, agitating it as they rise. |
| 2. | to reach or be brought to the boiling point: When the water boils, add the meat and cabbage. |
| 3. | to be in an agitated or violent state: The sea boiled in the storm. |
| 4. | to be deeply stirred or upset. |
| 5. | to contain, or be contained in, a liquid that boils: The kettle is boiling. The vegetables are boiling. |
| 6. | to cause to boil or to bring to the boiling point: Boil two cups of water. |
| 7. | to cook (something) in boiling water: to boil eggs. |
| 8. | to separate (sugar, salt, etc.) from a solution containing it by boiling off the liquid. |
| 9. | the act or an instance of boiling. |
| 10. | the state or condition of boiling: He brought a kettle of water to a boil. |
| 11. | an area of agitated, swirling, bubbling water, as part of a rapids. |
| 12. | Also called blow. Civil Engineering. an unwanted flow of water and solid matter into an excavation, due to excessive outside water pressure. |
| 13. | boil down,
|
| 14. | boil over,
|
| 15. | boil off, Textiles.
|

"I am impatient, and my blood boyls high." [Otway, "Alcibiades," 1675]Boiler in the steam engine sense is from 1757; boilermaker "shot of whiskey with a glass of beer" is short for boilermaker's delight (1910), strong cheap whiskey, so called in jest from the notion that it would clean the scales from the interior of a boiler.
boil (boil)
n.
A painful, circumscribed pus-filled inflammation of the skin and subcutaneous tissue usually caused by a local staphylococcal infection. Also called furuncle.
boil down
Simplify, summarize, or shorten, as in John finally managed to boil his thesis down to 200 pages.
boil down to. Be reducible to basic elements, be equivalent to. For example, What this issue boils down to is that the council doesn't want to spend more money. These metaphoric usages allude to reducing and concentrating a substance by boiling off liquid. [Late 1800s]