"neutron matter" meaning in English

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  "lang_code": "en",
  "pos": "noun",
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        {
          "kind": "topical",
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          "name": "Neutron",
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        {
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          "name": "Neutron stars",
          "orig": "en:Neutron stars",
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      "glosses": [
        "Matter consisting entirely of neutrons."
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      "id": "en-neutron_matter-en-noun-dth1nO33",
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          "word": "neutronium"
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        "neutron matter"
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  "word": "neutron matter"
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  "lang_code": "en",
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        "Matter consisting entirely of neutrons."
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  "word": "neutron matter"
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