"Müller-Lyer illusion" meaning in English

{
  "etymology_text": "Devised by Franz Carl Müller-Lyer (1857–1916), a German sociologist, in 1889.",
  "forms": [
    {
      "form": "Müller-Lyer illusions",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "Müller-Lyer illusion (plural Müller-Lyer illusions)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
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          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
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          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Optical illusions",
          "orig": "en:Optical illusions",
          "parents": [
            "Vision",
            "Senses",
            "Perception",
            "Body",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "An optical illusion consisting of a stylized arrow whose midpoint appears to be closer to the tail end."
      ],
      "id": "en-Müller-Lyer_illusion-en-noun-Jeeyza25",
      "links": [
        [
          "optical illusion",
          "optical illusion"
        ],
        [
          "stylized",
          "stylized"
        ],
        [
          "arrow",
          "arrow"
        ],
        [
          "midpoint",
          "midpoint"
        ],
        [
          "tail",
          "tail"
        ]
      ],
      "wikipedia": [
        "Müller-Lyer illusion"
      ]
    }
  ],
  "word": "Müller-Lyer illusion"
}

{
  "etymology_text": "Devised by Franz Carl Müller-Lyer (1857–1916), a German sociologist, in 1889.",
  "forms": [
    {
      "form": "Müller-Lyer illusions",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "Müller-Lyer illusion (plural Müller-Lyer illusions)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English eponyms",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms spelled with Ü",
        "English terms spelled with ◌̈",
        "Pages with 1 entry",
        "Pages with entries",
        "en:Optical illusions"
      ],
      "glosses": [
        "An optical illusion consisting of a stylized arrow whose midpoint appears to be closer to the tail end."
      ],
      "links": [
        [
          "optical illusion",
          "optical illusion"
        ],
        [
          "stylized",
          "stylized"
        ],
        [
          "arrow",
          "arrow"
        ],
        [
          "midpoint",
          "midpoint"
        ],
        [
          "tail",
          "tail"
        ]
      ],
      "wikipedia": [
        "Müller-Lyer illusion"
      ]
    }
  ],
  "word": "Müller-Lyer illusion"
}