Heart and soul Meaning, Definition & Usage

1. noun the choicest or most essential or most vital part of some idea or experience
   kernel; substance; center; centre; nitty-gritty; essence; sum; meat; heart; pith; nub; core; inwardness; marrow; gist.
   
   • the gist of the prosecutor's argument
   • the heart and soul of the Republican Party
   • the nub of the story
2. adverb with complete faith
   body and soul.
   
   • she was with him heart and soul

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