"elementary substance" meaning in English

{
  "forms": [
    {
      "form": "elementary substances",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "elementary substance (plural elementary substances)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "antonyms": [
        {
          "word": "chemical compound"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Entries with translation boxes",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Finnish translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with French translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Italian translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Polish translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Russian translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Chemical elements",
          "orig": "en:Chemical elements",
          "parents": [
            "Matter",
            "Chemistry",
            "Nature",
            "Sciences",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "A pure chemical substance consisting of a single element (e.g. hydrogen gas)."
      ],
      "id": "en-elementary_substance-en-noun-A74Zbkif",
      "translations": [
        {
          "code": "fi",
          "lang": "Finnish",
          "sense": "pure chemical substance consisting of a single element",
          "word": "alkuaine"
        },
        {
          "code": "fr",
          "lang": "French",
          "sense": "pure chemical substance consisting of a single element",
          "tags": [
            "masculine"
          ],
          "word": "corps simple"
        },
        {
          "code": "it",
          "lang": "Italian",
          "sense": "pure chemical substance consisting of a single element",
          "tags": [
            "feminine"
          ],
          "word": "sostanza semplice"
        },
        {
          "code": "pl",
          "lang": "Polish",
          "sense": "pure chemical substance consisting of a single element",
          "tags": [
            "masculine"
          ],
          "word": "pierwiastek"
        },
        {
          "code": "ru",
          "lang": "Russian",
          "roman": "prostóje veščestvó",
          "sense": "pure chemical substance consisting of a single element",
          "tags": [
            "neuter"
          ],
          "word": "просто́е вещество́"
        }
      ]
    }
  ],
  "word": "elementary substance"
}

{
  "forms": [
    {
      "form": "elementary substances",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "elementary substance (plural elementary substances)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "antonyms": [
        {
          "word": "chemical compound"
        }
      ],
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "Entries with translation boxes",
        "Pages with 1 entry",
        "Pages with entries",
        "Terms with Finnish translations",
        "Terms with French translations",
        "Terms with Italian translations",
        "Terms with Polish translations",
        "Terms with Russian translations",
        "en:Chemical elements"
      ],
      "glosses": [
        "A pure chemical substance consisting of a single element (e.g. hydrogen gas)."
      ]
    }
  ],
  "translations": [
    {
      "code": "fi",
      "lang": "Finnish",
      "sense": "pure chemical substance consisting of a single element",
      "word": "alkuaine"
    },
    {
      "code": "fr",
      "lang": "French",
      "sense": "pure chemical substance consisting of a single element",
      "tags": [
        "masculine"
      ],
      "word": "corps simple"
    },
    {
      "code": "it",
      "lang": "Italian",
      "sense": "pure chemical substance consisting of a single element",
      "tags": [
        "feminine"
      ],
      "word": "sostanza semplice"
    },
    {
      "code": "pl",
      "lang": "Polish",
      "sense": "pure chemical substance consisting of a single element",
      "tags": [
        "masculine"
      ],
      "word": "pierwiastek"
    },
    {
      "code": "ru",
      "lang": "Russian",
      "roman": "prostóje veščestvó",
      "sense": "pure chemical substance consisting of a single element",
      "tags": [
        "neuter"
      ],
      "word": "просто́е вещество́"
    }
  ],
  "word": "elementary substance"
}