"carefullest" meaning in English

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  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
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      "examples": [
        {
          "ref": "1945, John Betjeman, A Subaltern's Love Song:",
          "text": "Love-thirty, love-forty, oh! weakness of joy, / The speed of a swallow, the grace of a boy, / With carefullest carelessness, gaily you won, / I am weak from your loveliness, Joan Hunter Dunn.",
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      "form_of": [
        {
          "extra": "most careful",
          "word": "careful"
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      "glosses": [
        "superlative form of careful: most careful"
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  "word": "carefullest"
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  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
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      "examples": [
        {
          "ref": "1945, John Betjeman, A Subaltern's Love Song:",
          "text": "Love-thirty, love-forty, oh! weakness of joy, / The speed of a swallow, the grace of a boy, / With carefullest carelessness, gaily you won, / I am weak from your loveliness, Joan Hunter Dunn.",
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      "form_of": [
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          "extra": "most careful",
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        "superlative form of careful: most careful"
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        "form-of",
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  "word": "carefullest"
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