noun a small group of indispensable persons or things.
— synonyms: nucleus, core_group
noun the center of an object.
noun the central part of the Earth.
noun the choicest or most essential or most vital part of some idea or experience.
— synonyms: kernel, substance, center, centre, essence, gist, heart, heart_and_soul
noun a cylindrical sample of soil or rock obtained with a hollow drill.
noun an organization founded by James Leonard Farmer in 1942 to work for racial equality.
— synonyms: Congress_of_Racial_Equality
noun the central meaning or theme of a speech or literary work.
— synonyms: effect, essence, burden, gist
noun (computer science) a tiny ferrite toroid formerly used in a random access memory to store one bit of data.
— synonyms: magnetic_core
noun the chamber of a nuclear reactor containing the fissile material where the reaction takes place.
noun a bar of magnetic material (as soft iron) that passes through a coil and serves to increase the inductance of the coil.