"cerulean blue" meaning in English

{
  "forms": [
    {
      "form": "cerulean blues",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "-",
        "2": "s"
      },
      "expansion": "cerulean blue (usually uncountable, plural cerulean blues)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Blues",
          "orig": "en:Blues",
          "parents": [
            "Colors",
            "Light",
            "Vision",
            "Energy",
            "Senses",
            "Nature",
            "Perception",
            "All topics",
            "Body",
            "Fundamental",
            "Human"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "1951 January, “The Inner Circle and its Rolling Stock”, in Railway Magazine, page 59",
          "text": "[…] the cars were painted in \"Underground\" colours with red and cream (later all red) exteriors, and cerulean blue and cream interiors.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A greenish blue pigment / colour."
      ],
      "id": "en-cerulean_blue-en-noun-HlyEiwqC",
      "links": [
        [
          "greenish",
          "greenish"
        ],
        [
          "blue",
          "blue"
        ],
        [
          "pigment",
          "pigment"
        ],
        [
          "colour",
          "colour"
        ]
      ],
      "synonyms": [
        {
          "word": "coelin"
        }
      ],
      "tags": [
        "uncountable",
        "usually"
      ]
    }
  ],
  "word": "cerulean blue"
}

{
  "forms": [
    {
      "form": "cerulean blues",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "-",
        "2": "s"
      },
      "expansion": "cerulean blue (usually uncountable, plural cerulean blues)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms with quotations",
        "English uncountable nouns",
        "en:Blues"
      ],
      "examples": [
        {
          "ref": "1951 January, “The Inner Circle and its Rolling Stock”, in Railway Magazine, page 59",
          "text": "[…] the cars were painted in \"Underground\" colours with red and cream (later all red) exteriors, and cerulean blue and cream interiors.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A greenish blue pigment / colour."
      ],
      "links": [
        [
          "greenish",
          "greenish"
        ],
        [
          "blue",
          "blue"
        ],
        [
          "pigment",
          "pigment"
        ],
        [
          "colour",
          "colour"
        ]
      ],
      "tags": [
        "uncountable",
        "usually"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "coelin"
    }
  ],
  "word": "cerulean blue"
}