"Planck length" meaning in English

{
  "etymology_text": "Named after Max Planck, who defined it.",
  "forms": [
    {
      "form": "Planck lengths",
      "tags": [
        "plural"
      ]
    }
  ],
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      "expansion": "Planck length (plural Planck lengths)",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
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        {
          "kind": "other",
          "name": "English entries with incorrect language header",
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          "name": "Physics",
          "orig": "en:Physics",
          "parents": [
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      ],
      "glosses": [
        "A unit of length, believed to be the scale at which quantum gravity effects become significant, that is defined in terms of the speed of light, the gravitational constant and the reduced Planck's constant, namely: ℓ_P=√hbar Gc³≈1.616 252(81)×10⁻³⁵ mbox meters"
      ],
      "id": "en-Planck_length-en-noun-8-iAycgR",
      "links": [
        [
          "physics",
          "physics"
        ],
        [
          "length",
          "length"
        ],
        [
          "speed of light",
          "speed of light"
        ],
        [
          "gravitational constant",
          "gravitational constant"
        ],
        [
          "Planck's constant",
          "Planck's constant"
        ]
      ],
      "raw_glosses": [
        "(physics) A unit of length, believed to be the scale at which quantum gravity effects become significant, that is defined in terms of the speed of light, the gravitational constant and the reduced Planck's constant, namely: ℓ_P=√hbar Gc³≈1.616 252(81)×10⁻³⁵ mbox meters"
      ],
      "related": [
        {
          "word": "Planck scale"
        },
        {
          "word": "Planck time"
        },
        {
          "word": "Planck unit"
        },
        {
          "word": "superstring"
        }
      ],
      "topics": [
        "natural-sciences",
        "physical-sciences",
        "physics"
      ],
      "wikipedia": [
        "Max Planck",
        "Planck length"
      ]
    }
  ],
  "word": "Planck length"
}

{
  "etymology_text": "Named after Max Planck, who defined it.",
  "forms": [
    {
      "form": "Planck lengths",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "Planck length (plural Planck lengths)",
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    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "related": [
    {
      "word": "Planck scale"
    },
    {
      "word": "Planck time"
    },
    {
      "word": "Planck unit"
    },
    {
      "word": "superstring"
    }
  ],
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        "en:Physics"
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      "glosses": [
        "A unit of length, believed to be the scale at which quantum gravity effects become significant, that is defined in terms of the speed of light, the gravitational constant and the reduced Planck's constant, namely: ℓ_P=√hbar Gc³≈1.616 252(81)×10⁻³⁵ mbox meters"
      ],
      "links": [
        [
          "physics",
          "physics"
        ],
        [
          "length",
          "length"
        ],
        [
          "speed of light",
          "speed of light"
        ],
        [
          "gravitational constant",
          "gravitational constant"
        ],
        [
          "Planck's constant",
          "Planck's constant"
        ]
      ],
      "raw_glosses": [
        "(physics) A unit of length, believed to be the scale at which quantum gravity effects become significant, that is defined in terms of the speed of light, the gravitational constant and the reduced Planck's constant, namely: ℓ_P=√hbar Gc³≈1.616 252(81)×10⁻³⁵ mbox meters"
      ],
      "topics": [
        "natural-sciences",
        "physical-sciences",
        "physics"
      ],
      "wikipedia": [
        "Max Planck",
        "Planck length"
      ]
    }
  ],
  "word": "Planck length"
}