Definition of 'heart and soul'

Noun

1. 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"
      Synonyms: kernel substance core center essence gist heart inwardness marrow meat nub pith sum nitty-gritty

Adverb

1. with complete faith; "she was with him heart and soul"
      Synonyms: body and soul

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