What is the meaning of core?

noun

• A small group of indispensable persons or things.
  • usage: "five periodicals make up the core of their publishing program"
  • synonyms: nucleus, core group
• The center of an object.
  • usage: "the ball has a titanium core"
• The central part of the Earth.
• The choicest or most essential or most vital part of some idea or experience.
  • usage: "the gist of the prosecutor's argument"; "the heart and soul of the Republican Party"; "the nub of the story"
  • synonyms: kernel, substance, center, centre, essence, gist, heart, heart and soul, inwardness, marrow, meat, nub, pith, sum, nitty-gritty
• A cylindrical sample of soil or rock obtained with a hollow drill.
• An organization founded by James Leonard Farmer in 1942 to work for racial equality.
  • synonyms: Congress of Racial Equality
• The central meaning or theme of a speech or literary work.
  • synonyms: effect, essence, burden, gist
• Computer science. ( a tiny ferrite toroid formerly used in a random access memory to store one bit of data; now superseded by semiconductor memories)
  • usage: "each core has three wires passing through it, providing the means to select and detect the contents of each bit"
  • synonyms: magnetic core
• The chamber of a nuclear reactor containing the fissile material where the reaction takes place.
• A bar of magnetic material (as soft iron) that passes through a coil and serves to increase the inductance of the coil.

verb

• Remove the core or center from.
  • usage: "core an apple"