"track mark" meaning in English

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      "expansion": "track mark",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
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          "source": "w"
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      "form_of": [
        {
          "word": "track marks"
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      ],
      "glosses": [
        "singular of track marks"
      ],
      "id": "en-track_mark-en-noun-Gkg5bj2H",
      "links": [
        [
          "track marks",
          "track marks#English"
        ]
      ],
      "raw_glosses": [
        "(uncommon) singular of track marks"
      ],
      "tags": [
        "form-of",
        "singular",
        "uncommon"
      ]
    }
  ],
  "word": "track mark"
}

{
  "head_templates": [
    {
      "args": {
        "1": "?"
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      "expansion": "track mark",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English nouns with unknown or uncertain plurals",
        "English terms with uncommon senses"
      ],
      "form_of": [
        {
          "word": "track marks"
        }
      ],
      "glosses": [
        "singular of track marks"
      ],
      "links": [
        [
          "track marks",
          "track marks#English"
        ]
      ],
      "raw_glosses": [
        "(uncommon) singular of track marks"
      ],
      "tags": [
        "form-of",
        "singular",
        "uncommon"
      ]
    }
  ],
  "word": "track mark"
}