n a small group of indispensable persons or things n the center of an object n the central part of the Earth n the choicest or most essential or most vital part of some idea or experience n a cylindrical sample of soil or rock obtained with a hollow drill n an organization founded by James Leonard Farmer in 1942 to work for racial equality n the central meaning or theme of a speech or literary work n (computer science) a tiny ferrite toroid formerly used in a random access memory to store one bit of data
