"null matrix" meaning in All languages combined

{
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    {
      "form": "null matrices",
      "tags": [
        "plural"
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      "form": "null matrixes",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "A zero matrix."
      ],
      "id": "en-null_matrix-en-noun-F3Geg3aI",
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          "zero matrix",
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      "raw_glosses": [
        "(linear algebra) A zero matrix."
      ],
      "topics": [
        "linear-algebra",
        "mathematics",
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  "word": "null matrix"
}

{
  "forms": [
    {
      "form": "null matrices",
      "tags": [
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  ],
  "lang": "English",
  "lang_code": "en",
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        "(linear algebra) A zero matrix."
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  "word": "null matrix"
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