"Berlin blue" meaning in English

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  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "Synonym of Prussian blue"
      ],
      "id": "en-Berlin_blue-en-noun-pgpGnLKl",
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          "word": "Prussian blue"
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  "word": "Berlin blue"
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  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "Synonym of Prussian blue"
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          "word": "Prussian blue"
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  "word": "Berlin blue"
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