せいしんせいい

誠 心 誠 意

  1. adverb (fukushi), noun (common) (futsuumeishi), nouns which may take the genitive case particle 'no'

    in all sincerity, with one's whole heart, whole-hearted devotion
    yojijukugo

    • 彼は誠心誠意、彼女に尽くした。
      He devoted himself whole-heartedly to her.