"Black Belt" meaning in English

{
  "forms": [
    {
      "form": "Black Belts",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "head": "Black Belt"
      },
      "expansion": "Black Belt (plural Black Belts)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "black belt"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "2016 December 27, Josh Katz, “‘Duck Dynasty’ vs. ‘Modern Family’: 50 Maps of the U.S. Cultural Divide”, in The New York Times, →ISSN",
          "text": "Together they reveal a national culture split among three regions: cities and their suburbs; rural areas; and what we’re calling the extended Black Belt — a swath that extends from the Mississippi River along the Eastern Seaboard up to Washington, but also including city centers and other places with large nonwhite populations.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Alternative letter-case form of black belt"
      ],
      "id": "en-Black_Belt-en-noun-yiScVktE",
      "links": [
        [
          "black belt",
          "black belt#English"
        ]
      ],
      "tags": [
        "alt-of"
      ]
    }
  ],
  "word": "Black Belt"
}

{
  "forms": [
    {
      "form": "Black Belts",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "head": "Black Belt"
      },
      "expansion": "Black Belt (plural Black Belts)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "black belt"
        }
      ],
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms with quotations"
      ],
      "examples": [
        {
          "ref": "2016 December 27, Josh Katz, “‘Duck Dynasty’ vs. ‘Modern Family’: 50 Maps of the U.S. Cultural Divide”, in The New York Times, →ISSN",
          "text": "Together they reveal a national culture split among three regions: cities and their suburbs; rural areas; and what we’re calling the extended Black Belt — a swath that extends from the Mississippi River along the Eastern Seaboard up to Washington, but also including city centers and other places with large nonwhite populations.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Alternative letter-case form of black belt"
      ],
      "links": [
        [
          "black belt",
          "black belt#English"
        ]
      ],
      "tags": [
        "alt-of"
      ]
    }
  ],
  "word": "Black Belt"
}