Core n. 1.The heart or inner part of a thing, as of a column, wall, rope, of a boil, etc.; especially, the central part of fruit, containing the kernels or seeds; as, the core of an apple or quince. "A fever at the core, Fatal to him who bears, to all who ever bore."
2.The center or inner part, as of an open space; as, the core of a square. (Obs.)
3.The most important part of a thing; the essence; as, the core of a subject; also used attributively, as the core curriculum at a college.
4.(Founding) The portion of a mold which shapes the interior of a cylinder, tube, or other hollow casting, or which makes a hole in or through a casting; a part of the mold, made separate from and inserted in it, for shaping some part of the casting, the form of which is not determined by that of the pattern.
5.A disorder of sheep occasioned by worms in the liver. (Prov. Eng.)
6.(Anat.) The bony process which forms the central axis of the horns in many animals.
7.(Elec.) A mass of iron or other ferrous metal, forming the central part of an electromagnet, such as those upon which the conductor of an armature, a transformer, or an induction coil is wound. Note: The presence of the iron intensifies the magnetic field created by a a current passing through the windings.
8.(mining) A sample of earth or rock extracted from underground by a drilling device in such a manner that the layers of rock are preserved in the same order as they exist underground; as, to drill a core; to extract a core. The sample is typically removed with a rotating drill bit having a hollow center, and is thus shaped like a cylinder.
9.(Computers) The main working memory of a digital computer system, which typically retains the program code being executed as well as the data structures that are manipulated by the program. Contrasted to ROM and data storage device. Note: The term was applied originally to the main memory, consisting of small ferromagnetic rings, that were used to store data in older computers, where each ring representing one bit of information by virtue of its state of magnetization. They were superseded by electronic data storage devices.
Synonyms: core memory, random access memory, RAM
10.(Geol.) The central part of the earth, believed to be a sphere with a radius of about 2100 miles, and composed primarily of molten iron with some nickel. It is distinguished from the crust and mantle.
11.(Engineering) The central part of a nuclear reactor, containing the fissionable fuel.
Core box (Founding), a box or mold, usually divisible, in which cores are molded.
Core print (Founding), a projecting piece on a pattern which forms, in the mold, an impression for holding in place or steadying a core.
Core dump See core dump in the vocabulary. 
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