"size zero" meaning in English

{
  "forms": [
    {
      "form": "size zeros",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "~"
      },
      "expansion": "size zero (countable and uncountable, plural size zeros)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "American English",
          "parents": [],
          "source": "w"
        },
        {
          "_dis": "100 0",
          "kind": "topical",
          "langcode": "en",
          "name": "Size",
          "orig": "en:Size",
          "parents": [
            "Nature",
            "All topics",
            "Fundamental"
          ],
          "source": "w+disamb"
        }
      ],
      "glosses": [
        "The smallest size of women's clothing"
      ],
      "id": "en-size_zero-en-noun-ptwvnyKR",
      "raw_glosses": [
        "(US) The smallest size of women's clothing"
      ],
      "tags": [
        "US",
        "countable",
        "uncountable"
      ]
    },
    {
      "categories": [
        {
          "_dis": "17 83",
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        },
        {
          "_dis": "10 90",
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w+disamb"
        },
        {
          "_dis": "7 93",
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w+disamb"
        },
        {
          "_dis": "18 82",
          "kind": "topical",
          "langcode": "en",
          "name": "Zero",
          "orig": "en:Zero",
          "parents": [
            "Numbers",
            "All topics",
            "Terms by semantic function",
            "Fundamental"
          ],
          "source": "w+disamb"
        }
      ],
      "glosses": [
        "A woman with a very low body mass index, especially such a fashion model"
      ],
      "id": "en-size_zero-en-noun-YLwpGD45",
      "links": [
        [
          "woman",
          "woman"
        ],
        [
          "body mass index",
          "body mass index"
        ],
        [
          "fashion",
          "fashion"
        ],
        [
          "model",
          "model"
        ]
      ],
      "raw_glosses": [
        "(informal) A woman with a very low body mass index, especially such a fashion model"
      ],
      "tags": [
        "countable",
        "informal",
        "uncountable"
      ]
    }
  ],
  "wikipedia": [
    "size zero"
  ],
  "word": "size zero"
}

{
  "categories": [
    "English countable nouns",
    "English entries with incorrect language header",
    "English lemmas",
    "English multiword terms",
    "English nouns",
    "English uncountable nouns",
    "Pages with 1 entry",
    "Pages with entries",
    "en:Size",
    "en:Zero"
  ],
  "forms": [
    {
      "form": "size zeros",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "~"
      },
      "expansion": "size zero (countable and uncountable, plural size zeros)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "American English"
      ],
      "glosses": [
        "The smallest size of women's clothing"
      ],
      "raw_glosses": [
        "(US) The smallest size of women's clothing"
      ],
      "tags": [
        "US",
        "countable",
        "uncountable"
      ]
    },
    {
      "categories": [
        "English informal terms"
      ],
      "glosses": [
        "A woman with a very low body mass index, especially such a fashion model"
      ],
      "links": [
        [
          "woman",
          "woman"
        ],
        [
          "body mass index",
          "body mass index"
        ],
        [
          "fashion",
          "fashion"
        ],
        [
          "model",
          "model"
        ]
      ],
      "raw_glosses": [
        "(informal) A woman with a very low body mass index, especially such a fashion model"
      ],
      "tags": [
        "countable",
        "informal",
        "uncountable"
      ]
    }
  ],
  "wikipedia": [
    "size zero"
  ],
  "word": "size zero"
}