"untrackable" meaning in English

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "un",
        "3": "trackable"
      },
      "expansion": "un- + trackable",
      "name": "prefix"
    }
  ],
  "etymology_text": "un- + trackable",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "untrackable (not comparable)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English terms prefixed with un-",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "text": "Untrackable debris is a hazard in space travel."
        }
      ],
      "glosses": [
        "Not trackable; incapable of being tracked."
      ],
      "id": "en-untrackable-en-adj-1I8XiUlX",
      "links": [
        [
          "trackable",
          "trackable"
        ],
        [
          "track",
          "track"
        ]
      ],
      "synonyms": [
        {
          "word": "nontrackable"
        }
      ],
      "tags": [
        "not-comparable"
      ]
    }
  ],
  "word": "untrackable"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "un",
        "3": "trackable"
      },
      "expansion": "un- + trackable",
      "name": "prefix"
    }
  ],
  "etymology_text": "un- + trackable",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "untrackable (not comparable)",
      "name": "en-adj"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "adj",
  "senses": [
    {
      "categories": [
        "English adjectives",
        "English entries with incorrect language header",
        "English lemmas",
        "English terms prefixed with un-",
        "English uncomparable adjectives"
      ],
      "examples": [
        {
          "text": "Untrackable debris is a hazard in space travel."
        }
      ],
      "glosses": [
        "Not trackable; incapable of being tracked."
      ],
      "links": [
        [
          "trackable",
          "trackable"
        ],
        [
          "track",
          "track"
        ]
      ],
      "tags": [
        "not-comparable"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "nontrackable"
    }
  ],
  "word": "untrackable"
}