core
core / kôr/ • n. 1. the tough central part of various fruits, containing the seeds: an apple core.2. the central or most important part of something, in particular: ∎ [often as adj.] the part of something that is central to its existence or character: managers can concentrate on their core activities | the plan has the interests of children at its core. ∎ an important or unchanging group of people forming the central part of a larger body. ∎ the dense central region of a planet, esp. the nickel–iron inner part of the earth. ∎ the central part of a nuclear reactor, which contains the fissile material. ∎ a tiny ring of magnetic material used in a computer memory to store one bit of data, now superseded by semiconductor memories. ∎ the inner strand of an electrical cable or rope. ∎ a piece of soft iron forming the center of an electromagnet or an induction coil. ∎ an internal mold filling a space to be left hollow in a casting. ∎ a cylindrical sample of rock, ice, or other material obtained by boring with a hollow drill. ∎ Archaeol. a piece of flint from which flakes or blades have been removed.• v. [tr.] remove the tough central part and seeds from (a fruit).DERIVATIVES: cor·er n.