"Indian file" meaning in English

{
  "etymology_text": "Attested since the 18th century, as Native Americans traversed woods in this way.",
  "head_templates": [
    {
      "args": {
        "1": "?"
      },
      "expansion": "Indian file",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "American English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "1791, Voyages And Travels Of An Indian Interpreter And Trader, page 69",
          "text": "In about an hour they returned very much intoxicated, singing their dead war songs, and every warrior naked, painted black from head to foot: as they approached the house in Indian file, each one repeated the following words […]",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Single file."
      ],
      "id": "en-Indian_file-en-noun-qO6VIINE",
      "links": [
        [
          "Single file",
          "single file"
        ]
      ],
      "raw_glosses": [
        "(especially US, uncommon) Single file."
      ],
      "tags": [
        "US",
        "especially",
        "uncommon"
      ]
    }
  ],
  "word": "Indian file"
}

{
  "etymology_text": "Attested since the 18th century, as Native Americans traversed woods in this way.",
  "head_templates": [
    {
      "args": {
        "1": "?"
      },
      "expansion": "Indian file",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "American English",
        "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 quotations",
        "English terms with uncommon senses"
      ],
      "examples": [
        {
          "ref": "1791, Voyages And Travels Of An Indian Interpreter And Trader, page 69",
          "text": "In about an hour they returned very much intoxicated, singing their dead war songs, and every warrior naked, painted black from head to foot: as they approached the house in Indian file, each one repeated the following words […]",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Single file."
      ],
      "links": [
        [
          "Single file",
          "single file"
        ]
      ],
      "raw_glosses": [
        "(especially US, uncommon) Single file."
      ],
      "tags": [
        "US",
        "especially",
        "uncommon"
      ]
    }
  ],
  "word": "Indian file"
}