"subterraneous" meaning in English

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "la",
        "3": "subterrāneus"
      },
      "expansion": "Latin subterrāneus",
      "name": "bor"
    }
  ],
  "etymology_text": "From Latin subterrāneus.",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "subterraneous (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"
        }
      ],
      "derived": [
        {
          "word": "subterraneousness"
        }
      ],
      "examples": [
        {
          "ref": "1944 September and October, Charles E. Lee, “An Ancient Underground Railway”, in Railway Magazine, page 275",
          "text": "The 3-mile underground railway—or \"subterraneous wagonway\"—was begun about 1770 by Christopher Bedlington, and was therefore commonly known as Kitty's Drift.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Subterranean."
      ],
      "id": "en-subterraneous-en-adj-ctc0BrCb",
      "links": [
        [
          "Subterranean",
          "subterranean#English"
        ]
      ],
      "tags": [
        "not-comparable"
      ]
    }
  ],
  "word": "subterraneous"
}

{
  "derived": [
    {
      "word": "subterraneousness"
    }
  ],
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "la",
        "3": "subterrāneus"
      },
      "expansion": "Latin subterrāneus",
      "name": "bor"
    }
  ],
  "etymology_text": "From Latin subterrāneus.",
  "head_templates": [
    {
      "args": {
        "1": "-"
      },
      "expansion": "subterraneous (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 borrowed from Latin",
        "English terms derived from Latin",
        "English terms with quotations",
        "English uncomparable adjectives"
      ],
      "examples": [
        {
          "ref": "1944 September and October, Charles E. Lee, “An Ancient Underground Railway”, in Railway Magazine, page 275",
          "text": "The 3-mile underground railway—or \"subterraneous wagonway\"—was begun about 1770 by Christopher Bedlington, and was therefore commonly known as Kitty's Drift.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Subterranean."
      ],
      "links": [
        [
          "Subterranean",
          "subterranean#English"
        ]
      ],
      "tags": [
        "not-comparable"
      ]
    }
  ],
  "word": "subterraneous"
}