the choicest or most essential or most vital part of some idea or experience; "the gist of the prosecutor's argument"; "the heart and soul of the Republican Party"; "the nub of the story"
何らかの考えや経験の中から選り抜きで、最も不可欠でまた最も重要な部分
core
a cylindrical sample of soil or rock obtained with a hollow drill
(computer science) a tiny ferrite toroid formerly used in a random access memory to store one bit of data; now superseded by semiconductor memories; "each core has three wires passing through it, providing the means to select and detect the contents of each bit"