"purely imaginary number" meaning in English

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  "forms": [
    {
      "form": "purely imaginary numbers",
      "tags": [
        "plural"
      ]
    }
  ],
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        "head": "purely imaginary number"
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      "expansion": "purely imaginary number (plural purely imaginary numbers)",
      "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": [
            "Entries with incorrect language header",
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        {
          "kind": "topical",
          "langcode": "en",
          "name": "Complex analysis",
          "orig": "en:Complex analysis",
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            "Mathematics",
            "Formal sciences",
            "Sciences",
            "All topics",
            "Fundamental"
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        }
      ],
      "glosses": [
        "An imaginary number."
      ],
      "id": "en-purely_imaginary_number-en-noun-WFEECiXB",
      "links": [
        [
          "complex analysis",
          "complex analysis"
        ],
        [
          "imaginary number",
          "imaginary number"
        ]
      ],
      "raw_glosses": [
        "(complex analysis) An imaginary number."
      ],
      "topics": [
        "complex-analysis",
        "mathematics",
        "sciences"
      ]
    }
  ],
  "word": "purely imaginary number"
}

{
  "forms": [
    {
      "form": "purely imaginary numbers",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
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      },
      "expansion": "purely imaginary number (plural purely imaginary numbers)",
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
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        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
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        "en:Complex analysis"
      ],
      "glosses": [
        "An imaginary number."
      ],
      "links": [
        [
          "complex analysis",
          "complex analysis"
        ],
        [
          "imaginary number",
          "imaginary number"
        ]
      ],
      "raw_glosses": [
        "(complex analysis) An imaginary number."
      ],
      "topics": [
        "complex-analysis",
        "mathematics",
        "sciences"
      ]
    }
  ],
  "word": "purely imaginary number"
}