2. To be agitated like boiling water, by any other cause than heat; to bubble; to effervesce; as, the boiling waves. [ 1913 Webster ]

He maketh the deep to boil like a pot. Job xii. 31. [ 1913 Webster ]

3. To pass from a liquid to an aëriform state or vapor when heated; as, the water boils away. [ 1913 Webster ]

4. To be moved or excited with passion; to be hot or fervid; as, his blood boils with anger. [ 1913 Webster ]

Then boiled my breast with flame and burning wrath. Surrey. [ 1913 Webster ]

5. To be in boiling water, as in cooking; as, the potatoes are boiling. [ 1913 Webster ]

To boil away, to vaporize; to evaporate or be evaporated by the action of heat. --
To boil over, to run over the top of a vessel, as liquid when thrown into violent agitation by heat or other cause of effervescence; to be excited with ardor or passion so as to lose self-control. [ 1913 Webster ]

2. To form, or separate, by boiling or evaporation; as, to boil sugar or salt. [ 1913 Webster ]

3. To subject to the action of heat in a boiling liquid so as to produce some specific effect, as cooking, cleansing, etc.; as, to boil meat; to boil clothes. [ 1913 Webster ]

The stomach cook is for the hall,
And boileth meate for them all. Gower. [ 1913 Webster ]

4. To steep or soak in warm water. [ Obs. ] [ 1913 Webster ]

To try whether seeds be old or new, the sense can not inform; but if you boil them in water, the new seeds will sprout sooner. Bacon. [ 1913 Webster ]

To boil down, to reduce in bulk by boiling; as, to boil down sap or sirup. [ 1913 Webster ]

A blind boil, one that suppurates imperfectly, or fails to come to a head. --
Delhi boil (Med.), a peculiar affection of the skin, probably parasitic in origin, prevailing in India (as among the British troops) and especially at Delhi. [ 1913 Webster ]

2. A vessel in which any thing is boiled. [ 1913 Webster ]

☞ The word boiler is a generic term covering a great variety of kettles, saucepans, clothes boilers, evaporators, coppers, retorts, etc. [ 1913 Webster ]

3. (Mech.) A strong metallic vessel, usually of wrought iron plates riveted together, or a composite structure variously formed, in which steam is generated for driving engines, or for heating, cooking, or other purposes. [ 1913 Webster ]

☞ The earliest steam boilers were usually spheres or sections of spheres, heated wholly from the outside. Watt used the wagon boiler (shaped like the top of a covered wagon) which is still used with low pressures. Most of the boilers in present use may be classified as plain cylinder boilers, flue boilers, sectional and tubular boilers. [ 1913 Webster ]

Barrel of a boiler, the cylindrical part containing the flues. --
Boiler plate,
Boiler iron, plate or rolled iron of about a quarter to a half inch in thickness, used for making boilers and tanks, for covering ships, etc. --
Cylinder boiler, one which consists of a single iron cylinder. --
Flue boilers are usually single shells containing a small number of large flues, through which the heat either passes from the fire or returns to the chimney, and sometimes containing a fire box inclosed by water. --
Locomotive boiler, a boiler which contains an inclosed fire box and a large number of small flues leading to the chimney. --
Multiflue boiler. Same as Tubular boiler, below. --
Sectional boiler, a boiler composed of a number of sections, which are usually of small capacity and similar to, and connected with, each other. By multiplication of the sections a boiler of any desired capacity can be built up. --
Tubular boiler, a boiler containing tubes which form flues, and are surrounded by the water contained in the boiler. See Illust. of Steam boiler, under Steam. --
Tubulous boiler. See under Tubulous. See Tube, n., 6, and 1st Flue. [ 1913 Webster ]

Boiling point, the temperature at which a fluid is converted into vapor, with the phenomena of ebullition. This is different for different liquids, and for the same liquid under different pressures. For water, at the level of the sea, barometer 30 in., it is 212 ° Fahrenheit; for alcohol, 172.96°; for ether, 94.8°; for mercury, about 675°. The boiling point of water is lowered one degree Fahrenheit for about 550 feet of ascent above the level of the sea. --
Boiling spring, a spring which gives out very hot water, or water and steam, often ejecting it with much force; a geyser. --
To be at the boiling point, to be very angry. --
To keep the pot boiling, to keep going on actively, as in certain games. [ Colloq. ] [ 1913 Webster ]

2. Exposure to the action of a hot liquid. [ 1913 Webster ]

And lakes of bitumen rise boiling higher. Byron. [ 1913 Webster ]

2. emotionally hardened; -- used of persons.
Syn. -- callous, case-hardened, hardened. [ WordNet 1.5 ]

3. cooked until the yolk is solid; -- used of eggs; as, a breakfast of pancakes and hard-boiled eggs. [ WordNet 1.5 ]

Nor is discontent to keep the mind
Deep in its fountain, lest it overboil
In the hot throng. Byron. [ 1913 Webster ]

2. To boil in part; to cook partially by boiling. [ 1913 Webster ]

3. Hence: (Fig.) To do (something) only part way, or incompletely. Also used intransitively. [ PJC ]

2. Fig.: To make or to become hot. [ Obs. ] [ 1913 Webster ]

Some of his companions thereat reboyleth. Sir T. Elyot. [ 1913 Webster ]