"Diocletian window" meaning in English

{
  "forms": [
    {
      "form": "Diocletian windows",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
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      "args": {},
      "expansion": "Diocletian window (plural Diocletian windows)",
      "name": "en-noun"
    }
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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          "kind": "topical",
          "langcode": "en",
          "name": "Architecture",
          "orig": "en:Architecture",
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      "glosses": [
        "A large semicircular window, characteristic of the enormous public baths (thermae) of Ancient Rome."
      ],
      "id": "en-Diocletian_window-en-noun-x9aBXwWn",
      "links": [
        [
          "architecture",
          "architecture"
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      "raw_glosses": [
        "(architecture) A large semicircular window, characteristic of the enormous public baths (thermae) of Ancient Rome."
      ],
      "topics": [
        "architecture"
      ]
    }
  ],
  "word": "Diocletian window"
}

{
  "forms": [
    {
      "form": "Diocletian windows",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "Diocletian window (plural Diocletian windows)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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        "English countable nouns",
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        "en:Architecture"
      ],
      "glosses": [
        "A large semicircular window, characteristic of the enormous public baths (thermae) of Ancient Rome."
      ],
      "links": [
        [
          "architecture",
          "architecture"
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      ],
      "raw_glosses": [
        "(architecture) A large semicircular window, characteristic of the enormous public baths (thermae) of Ancient Rome."
      ],
      "topics": [
        "architecture"
      ]
    }
  ],
  "word": "Diocletian window"
}