"milliarcsecond" meaning in English

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  "etymology_text": "milli- + arcsecond",
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          "word": "milliarcsec"
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        "A unit of angle equal to one thousandth of an arcsecond (used especially in astronomy)"
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        "(metrology) A unit of angle equal to one thousandth of an arcsecond (used especially in astronomy)"
      ],
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  "word": "milliarcsecond"
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  "etymology_text": "milli- + arcsecond",
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        "(metrology) A unit of angle equal to one thousandth of an arcsecond (used especially in astronomy)"
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