"oxygen thief" meaning in English

{
  "etymology_text": "Suggesting that the person's breathing wastes oxygen that could be put to better use.",
  "forms": [
    {
      "form": "oxygen thieves",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "oxygen thieves"
      },
      "expansion": "oxygen thief (plural oxygen thieves)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "A useless person."
      ],
      "id": "en-oxygen_thief-en-noun-Q4MmRtwu",
      "links": [
        [
          "derogatory",
          "derogatory"
        ],
        [
          "useless",
          "useless#English"
        ]
      ],
      "raw_glosses": [
        "(informal, derogatory) A useless person."
      ],
      "related": [
        {
          "word": "waste of space"
        }
      ],
      "tags": [
        "derogatory",
        "informal"
      ]
    }
  ],
  "word": "oxygen thief"
}

{
  "etymology_text": "Suggesting that the person's breathing wastes oxygen that could be put to better use.",
  "forms": [
    {
      "form": "oxygen thieves",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "oxygen thieves"
      },
      "expansion": "oxygen thief (plural oxygen thieves)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "related": [
    {
      "word": "waste of space"
    }
  ],
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English derogatory terms",
        "English entries with incorrect language header",
        "English informal terms",
        "English lemmas",
        "English multiword terms",
        "English nouns"
      ],
      "glosses": [
        "A useless person."
      ],
      "links": [
        [
          "derogatory",
          "derogatory"
        ],
        [
          "useless",
          "useless#English"
        ]
      ],
      "raw_glosses": [
        "(informal, derogatory) A useless person."
      ],
      "tags": [
        "derogatory",
        "informal"
      ]
    }
  ],
  "word": "oxygen thief"
}