"Jordan's rule" meaning in English

{
  "etymology_text": "Named after American scientist David Starr Jordan (1851–1931).",
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      "expansion": "Jordan's rule",
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  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "glosses": [
        "An ecogeographic rule describing the inverse relationship between water temperature and meristic characteristics in various species of fish, including the fact that fin ray, vertebrae, or scale numbers increase with decreasing temperature."
      ],
      "id": "en-Jordan's_rule-en-name-S7nU-M~u",
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          "ecogeographic",
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          "inverse",
          "inverse"
        ],
        [
          "relationship",
          "relationship"
        ],
        [
          "water",
          "water"
        ],
        [
          "temperature",
          "temperature"
        ],
        [
          "meristic",
          "meristic"
        ],
        [
          "species",
          "species"
        ],
        [
          "fish",
          "fish"
        ]
      ]
    },
    {
      "categories": [
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          "_dis": "31 69",
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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            "Entries with language name categories using raw markup",
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          "_dis": "19 81",
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          "source": "w+disamb"
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      ],
      "glosses": [
        "An ecogeographic rule stating that, given any species in any region, the nearest related species is not likely to be found in the same region nor in a remote region, but in a neighbouring district separated from the first by a barrier of some sort."
      ],
      "id": "en-Jordan's_rule-en-name-Ewlxaqp7",
      "links": [
        [
          "ecogeographic",
          "ecogeographic"
        ],
        [
          "region",
          "region"
        ],
        [
          "barrier",
          "barrier"
        ]
      ],
      "synonyms": [
        {
          "word": "Jordan's law"
        }
      ]
    }
  ],
  "word": "Jordan's rule"
}

{
  "categories": [
    "English entries with incorrect language header",
    "English entries with language name categories using raw markup",
    "English eponyms",
    "English lemmas",
    "English multiword terms",
    "English proper nouns",
    "English terms with non-redundant non-automated sortkeys",
    "English uncountable nouns"
  ],
  "etymology_text": "Named after American scientist David Starr Jordan (1851–1931).",
  "head_templates": [
    {
      "args": {},
      "expansion": "Jordan's rule",
      "name": "en-prop"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "glosses": [
        "An ecogeographic rule describing the inverse relationship between water temperature and meristic characteristics in various species of fish, including the fact that fin ray, vertebrae, or scale numbers increase with decreasing temperature."
      ],
      "links": [
        [
          "ecogeographic",
          "ecogeographic"
        ],
        [
          "inverse",
          "inverse"
        ],
        [
          "relationship",
          "relationship"
        ],
        [
          "water",
          "water"
        ],
        [
          "temperature",
          "temperature"
        ],
        [
          "meristic",
          "meristic"
        ],
        [
          "species",
          "species"
        ],
        [
          "fish",
          "fish"
        ]
      ]
    },
    {
      "glosses": [
        "An ecogeographic rule stating that, given any species in any region, the nearest related species is not likely to be found in the same region nor in a remote region, but in a neighbouring district separated from the first by a barrier of some sort."
      ],
      "links": [
        [
          "ecogeographic",
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        ],
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          "region",
          "region"
        ],
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          "barrier"
        ]
      ],
      "synonyms": [
        {
          "word": "Jordan's law"
        }
      ]
    }
  ],
  "word": "Jordan's rule"
}