"aptychus" meaning in English

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        "3": "πτυχή",
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        "5": "fold, layer"
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      "expansion": "Ancient Greek πτυχή (ptukhḗ, “fold, layer”)",
      "name": "uder"
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  "etymology_text": "Modern Latin, from a- + Ancient Greek πτυχή (ptukhḗ, “fold, layer”).",
  "forms": [
    {
      "form": "aptychi",
      "tags": [
        "plural"
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  "lang_code": "en",
  "pos": "noun",
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          "name": "Animal body parts",
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          "kind": "lifeform",
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          "name": "Paleontology",
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          "ref": "2017, Danna Staaf, Squid Empire, ForeEdge, →ISBN, page 95:",
          "text": "It wasn't until the 1970s that paleontologists had amassed enough evidence to be certain that aptychi were modified lower jaws.",
          "type": "quote"
        }
      ],
      "glosses": [
        "A hard calcareous plate forming part of the body of an ammonite."
      ],
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          "calcareous",
          "calcareous"
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          "plate",
          "plate"
        ],
        [
          "ammonite",
          "ammonite"
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        "(paleontology) A hard calcareous plate forming part of the body of an ammonite."
      ],
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      "name": "uder"
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  "etymology_text": "Modern Latin, from a- + Ancient Greek πτυχή (ptukhḗ, “fold, layer”).",
  "forms": [
    {
      "form": "aptychi",
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        "plural"
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  "lang_code": "en",
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        "A hard calcareous plate forming part of the body of an ammonite."
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