"pit head" meaning in English

{
  "forms": [
    {
      "form": "pit heads",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "pit head (plural pit heads)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "extra": "sense 1",
          "word": "pithead"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "1949 January and February, F. G. Roe, “I Saw Three Englands–1”, in Railway Magazine, page 11:",
          "text": "The smoke-pall of industrial Lancashire hung over the landscape; perhaps slagscape would be a more fitting term. The general prospect was a succession of chimney-stacks, factories, pit-heads, slagheaps, junctions, sidings and coal wagons.",
          "type": "quote"
        }
      ],
      "glosses": [
        "Alternative form of pithead (sense 1)."
      ],
      "id": "en-pit_head-en-noun-YwgsGlSI",
      "links": [
        [
          "pithead",
          "pithead#English"
        ]
      ],
      "tags": [
        "alt-of",
        "alternative"
      ]
    }
  ],
  "word": "pit head"
}

{
  "forms": [
    {
      "form": "pit heads",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "pit head (plural pit heads)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "extra": "sense 1",
          "word": "pithead"
        }
      ],
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms with quotations",
        "Pages with 1 entry",
        "Pages with entries"
      ],
      "examples": [
        {
          "ref": "1949 January and February, F. G. Roe, “I Saw Three Englands–1”, in Railway Magazine, page 11:",
          "text": "The smoke-pall of industrial Lancashire hung over the landscape; perhaps slagscape would be a more fitting term. The general prospect was a succession of chimney-stacks, factories, pit-heads, slagheaps, junctions, sidings and coal wagons.",
          "type": "quote"
        }
      ],
      "glosses": [
        "Alternative form of pithead (sense 1)."
      ],
      "links": [
        [
          "pithead",
          "pithead#English"
        ]
      ],
      "tags": [
        "alt-of",
        "alternative"
      ]
    }
  ],
  "word": "pit head"
}