nitty-gritty


nitty-gritty (http://definr.com/nitty-gritty)

     n : 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" [syn: kernel, substance, core,
          center, essence, gist, heart, heart and soul,
         inwardness, marrow, meat, nub, pith, sum]