n. 1. One who boils. [ 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 ]

n. A sunken reef; esp., a coral reef on which the sea breaks heavily. [ Webster 1913 Suppl. ]

n. a loose protective smock worn over ordinary clothing for dirty work. [ British ]
Syn. -- overall, boilers suit. [ WordNet 1.5 ]

n. [ Cf. F. bouillerie. ] A place and apparatus for boiling, as for evaporating brine in salt making. [ 1913 Webster ]