"single track" meaning in English

{
  "forms": [
    {
      "form": "single tracks",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "single track (plural single tracks)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "singletrack"
        }
      ],
      "glosses": [
        "Alternative spelling of singletrack"
      ],
      "id": "en-single_track-en-noun-tjbqF0SF",
      "links": [
        [
          "singletrack",
          "singletrack#English"
        ]
      ],
      "tags": [
        "alt-of",
        "alternative"
      ]
    },
    {
      "categories": [
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Rail transportation",
          "orig": "en:Rail transportation",
          "parents": [
            "Transport",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        },
        {
          "_dis": "12 88",
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "11 89",
          "kind": "other",
          "name": "Entries with translation boxes",
          "parents": [],
          "source": "w+disamb"
        },
        {
          "_dis": "10 90",
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w+disamb"
        },
        {
          "_dis": "6 94",
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w+disamb"
        },
        {
          "_dis": "14 86",
          "kind": "other",
          "name": "Terms with Japanese translations",
          "parents": [],
          "source": "w+disamb"
        },
        {
          "_dis": "19 81",
          "kind": "other",
          "name": "Terms with Mandarin translations",
          "parents": [],
          "source": "w+disamb"
        }
      ],
      "glosses": [
        "A single rail line, where trains can only run in one direction at a time between passing points."
      ],
      "id": "en-single_track-en-noun-xRJDISme",
      "links": [
        [
          "rail transport",
          "rail transport"
        ],
        [
          "single",
          "single"
        ],
        [
          "rail",
          "rail"
        ],
        [
          "line",
          "line"
        ]
      ],
      "raw_glosses": [
        "(rail transport) A single rail line, where trains can only run in one direction at a time between passing points."
      ],
      "topics": [
        "rail-transport",
        "railways",
        "transport"
      ],
      "translations": [
        {
          "_dis1": "4 96",
          "code": "cmn",
          "lang": "Chinese Mandarin",
          "sense": "single rail line",
          "word": "單線"
        },
        {
          "_dis1": "4 96",
          "code": "cmn",
          "lang": "Chinese Mandarin",
          "roman": "dānxiàn",
          "sense": "single rail line",
          "word": "单线"
        },
        {
          "_dis1": "4 96",
          "alt": "たんせん",
          "code": "ja",
          "lang": "Japanese",
          "roman": "tansen",
          "sense": "single rail line",
          "word": "単線"
        }
      ]
    }
  ],
  "word": "single track"
}

{
  "categories": [
    "English countable nouns",
    "English entries with incorrect language header",
    "English lemmas",
    "English multiword terms",
    "English nouns",
    "Entries with translation boxes",
    "Pages with 1 entry",
    "Pages with entries",
    "Terms with Japanese translations",
    "Terms with Mandarin translations"
  ],
  "forms": [
    {
      "form": "single tracks",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "single track (plural single tracks)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "singletrack"
        }
      ],
      "glosses": [
        "Alternative spelling of singletrack"
      ],
      "links": [
        [
          "singletrack",
          "singletrack#English"
        ]
      ],
      "tags": [
        "alt-of",
        "alternative"
      ]
    },
    {
      "categories": [
        "en:Rail transportation"
      ],
      "glosses": [
        "A single rail line, where trains can only run in one direction at a time between passing points."
      ],
      "links": [
        [
          "rail transport",
          "rail transport"
        ],
        [
          "single",
          "single"
        ],
        [
          "rail",
          "rail"
        ],
        [
          "line",
          "line"
        ]
      ],
      "raw_glosses": [
        "(rail transport) A single rail line, where trains can only run in one direction at a time between passing points."
      ],
      "topics": [
        "rail-transport",
        "railways",
        "transport"
      ]
    }
  ],
  "translations": [
    {
      "code": "cmn",
      "lang": "Chinese Mandarin",
      "sense": "single rail line",
      "word": "單線"
    },
    {
      "code": "cmn",
      "lang": "Chinese Mandarin",
      "roman": "dānxiàn",
      "sense": "single rail line",
      "word": "单线"
    },
    {
      "alt": "たんせん",
      "code": "ja",
      "lang": "Japanese",
      "roman": "tansen",
      "sense": "single rail line",
      "word": "単線"
    }
  ],
  "word": "single track"
}