"by eye" meaning in English

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      "expansion": "by eye",
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  "lang_code": "en",
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      "examples": [
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          "ref": "1984, Andrew Barker, Greek Musical Writings: Volume 2, Harmonic and Acoustic Theory, page 277",
          "text": "Thus given a straight line it is very easy to construct a smaller or a greater than it by eye, not just because this is a broad sort of distinction, but because it also involves only one comparison.",
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        "By estimation, based on a visual inspection, without accurate measurement."
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          "estimation",
          "estimation"
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          "visual",
          "visual"
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          "inspection",
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          "accurate",
          "accurate"
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        [
          "measurement",
          "measurement"
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      ]
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  "word": "by eye"
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      "expansion": "by eye",
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  "lang_code": "en",
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        {
          "ref": "1984, Andrew Barker, Greek Musical Writings: Volume 2, Harmonic and Acoustic Theory, page 277",
          "text": "Thus given a straight line it is very easy to construct a smaller or a greater than it by eye, not just because this is a broad sort of distinction, but because it also involves only one comparison.",
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        }
      ],
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        "By estimation, based on a visual inspection, without accurate measurement."
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          "estimation",
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          "measurement"
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  "word": "by eye"
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