"imperfect time" meaning in English

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      "expansion": "imperfect time",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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        {
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          "langcode": "en",
          "name": "Music",
          "orig": "en:Music",
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            "Art",
            "Sound",
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      "examples": [
        {
          "text": "Coordinate term: perfect time"
        }
      ],
      "glosses": [
        "A system of timing in mensural notation in which a breve is equal to two semibreves."
      ],
      "id": "en-imperfect_time-en-noun-pMI-t2Du",
      "links": [
        [
          "music",
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        [
          "system",
          "system"
        ],
        [
          "timing",
          "timing"
        ],
        [
          "mensural notation",
          "mensural notation"
        ],
        [
          "breve",
          "breve"
        ],
        [
          "semibreve",
          "semibreve"
        ]
      ],
      "raw_glosses": [
        "(music, historical) A system of timing in mensural notation in which a breve is equal to two semibreves."
      ],
      "tags": [
        "historical"
      ],
      "topics": [
        "entertainment",
        "lifestyle",
        "music"
      ]
    }
  ],
  "word": "imperfect time"
}

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      "expansion": "imperfect time",
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  "lang_code": "en",
  "pos": "noun",
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        "en:Music"
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      "examples": [
        {
          "text": "Coordinate term: perfect time"
        }
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      "glosses": [
        "A system of timing in mensural notation in which a breve is equal to two semibreves."
      ],
      "links": [
        [
          "music",
          "music"
        ],
        [
          "system",
          "system"
        ],
        [
          "timing",
          "timing"
        ],
        [
          "mensural notation",
          "mensural notation"
        ],
        [
          "breve",
          "breve"
        ],
        [
          "semibreve",
          "semibreve"
        ]
      ],
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        "(music, historical) A system of timing in mensural notation in which a breve is equal to two semibreves."
      ],
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        "historical"
      ],
      "topics": [
        "entertainment",
        "lifestyle",
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  "word": "imperfect time"
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