"self-coloured" meaning in English

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "self-",
        "3": "coloured"
      },
      "expansion": "self- + coloured",
      "name": "af"
    }
  ],
  "etymology_text": "From self- + coloured.",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "self-coloured (not comparable)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English terms prefixed with self-",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "1961 October, “Car carriage by rail - at home and abroad: 1. New B.R. \"covered wagons\"”, in Trains Illustrated, page 594",
          "text": "The glass fibre body has the advantage of lightness and obviates the need for painting as the material is self-coloured in the standard B.R. maroon livery.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Of a single uniform colour."
      ],
      "id": "en-self-coloured-en-adj-Qxjax4Kw",
      "raw_glosses": [
        "(British spelling) Of a single uniform colour."
      ],
      "tags": [
        "UK",
        "not-comparable"
      ]
    }
  ],
  "word": "self-coloured"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "self-",
        "3": "coloured"
      },
      "expansion": "self- + coloured",
      "name": "af"
    }
  ],
  "etymology_text": "From self- + coloured.",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "self-coloured (not comparable)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        "British English forms",
        "English adjectives",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English terms prefixed with self-",
        "English terms with quotations",
        "English uncomparable adjectives"
      ],
      "examples": [
        {
          "ref": "1961 October, “Car carriage by rail - at home and abroad: 1. New B.R. \"covered wagons\"”, in Trains Illustrated, page 594",
          "text": "The glass fibre body has the advantage of lightness and obviates the need for painting as the material is self-coloured in the standard B.R. maroon livery.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Of a single uniform colour."
      ],
      "raw_glosses": [
        "(British spelling) Of a single uniform colour."
      ],
      "tags": [
        "UK",
        "not-comparable"
      ]
    }
  ],
  "word": "self-coloured"
}