"ionic radius" meaning in English

{
  "forms": [
    {
      "form": "ionic radii",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "ionic radii"
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      "expansion": "ionic radius (plural ionic radii)",
      "name": "en-noun"
    }
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
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        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
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          "source": "w"
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        {
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          "langcode": "en",
          "name": "Physics",
          "orig": "en:Physics",
          "parents": [
            "Sciences",
            "All topics",
            "Fundamental"
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          "source": "w"
        }
      ],
      "glosses": [
        "The measure of a monatomic ion in the structure of an ionic crystal."
      ],
      "id": "en-ionic_radius-en-noun-g0X3ffEy",
      "links": [
        [
          "physics",
          "physics"
        ],
        [
          "monatomic",
          "monatomic"
        ],
        [
          "ion",
          "ion"
        ],
        [
          "ionic crystal",
          "ionic crystal"
        ]
      ],
      "raw_glosses": [
        "(physics) The measure of a monatomic ion in the structure of an ionic crystal."
      ],
      "topics": [
        "natural-sciences",
        "physical-sciences",
        "physics"
      ]
    }
  ],
  "word": "ionic radius"
}

{
  "forms": [
    {
      "form": "ionic radii",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "ionic radii"
      },
      "expansion": "ionic radius (plural ionic radii)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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        "English multiword terms",
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      ],
      "glosses": [
        "The measure of a monatomic ion in the structure of an ionic crystal."
      ],
      "links": [
        [
          "physics",
          "physics"
        ],
        [
          "monatomic",
          "monatomic"
        ],
        [
          "ion",
          "ion"
        ],
        [
          "ionic crystal",
          "ionic crystal"
        ]
      ],
      "raw_glosses": [
        "(physics) The measure of a monatomic ion in the structure of an ionic crystal."
      ],
      "topics": [
        "natural-sciences",
        "physical-sciences",
        "physics"
      ]
    }
  ],
  "word": "ionic radius"
}