"echelle grating" meaning in English

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    {
      "form": "echelle gratings",
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  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "A form of diffraction grating optimized for high orders of diffraction"
      ],
      "id": "en-echelle_grating-en-noun-G9xDK5g6",
      "links": [
        [
          "physics",
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        [
          "diffraction grating",
          "diffraction grating"
        ],
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          "diffraction",
          "diffraction"
        ]
      ],
      "raw_glosses": [
        "(physics) A form of diffraction grating optimized for high orders of diffraction"
      ],
      "topics": [
        "natural-sciences",
        "physical-sciences",
        "physics"
      ]
    }
  ],
  "word": "echelle grating"
}

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    {
      "form": "echelle gratings",
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      "expansion": "echelle grating (plural echelle gratings)",
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  "lang_code": "en",
  "pos": "noun",
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      "glosses": [
        "A form of diffraction grating optimized for high orders of diffraction"
      ],
      "links": [
        [
          "physics",
          "physics"
        ],
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          "diffraction grating",
          "diffraction grating"
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          "diffraction",
          "diffraction"
        ]
      ],
      "raw_glosses": [
        "(physics) A form of diffraction grating optimized for high orders of diffraction"
      ],
      "topics": [
        "natural-sciences",
        "physical-sciences",
        "physics"
      ]
    }
  ],
  "word": "echelle grating"
}