"absolute blocking" meaning in English

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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "A system of managing trains that breaks the line into small segments, and if a train is in a segment, no other train may follow, unless the second train is following the first, with caution."
      ],
      "id": "en-absolute_blocking-en-noun-tn3faQ16",
      "qualifier": "railway",
      "raw_glosses": [
        "(railway) A system of managing trains that breaks the line into small segments, and if a train is in a segment, no other train may follow, unless the second train is following the first, with caution."
      ],
      "synonyms": [
        {
          "word": "block system"
        }
      ],
      "tags": [
        "uncountable"
      ],
      "translations": [
        {
          "code": "fi",
          "lang": "Finnish",
          "sense": "system of managing trains",
          "word": "suojastus"
        }
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/ˈæb.səˌlut ˈblɑk.ɪŋ/",
      "tags": [
        "US"
      ]
    },
    {
      "ipa": "/ˌæb.səˈljut ˈblɑk.ɪŋ/",
      "tags": [
        "US"
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    }
  ],
  "word": "absolute blocking"
}

{
  "head_templates": [
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      "expansion": "absolute blocking (uncountable)",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "A system of managing trains that breaks the line into small segments, and if a train is in a segment, no other train may follow, unless the second train is following the first, with caution."
      ],
      "qualifier": "railway",
      "raw_glosses": [
        "(railway) A system of managing trains that breaks the line into small segments, and if a train is in a segment, no other train may follow, unless the second train is following the first, with caution."
      ],
      "tags": [
        "uncountable"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/ˈæb.səˌlut ˈblɑk.ɪŋ/",
      "tags": [
        "US"
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    },
    {
      "ipa": "/ˌæb.səˈljut ˈblɑk.ɪŋ/",
      "tags": [
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  ],
  "synonyms": [
    {
      "word": "block system"
    }
  ],
  "translations": [
    {
      "code": "fi",
      "lang": "Finnish",
      "sense": "system of managing trains",
      "word": "suojastus"
    }
  ],
  "word": "absolute blocking"
}