"prog rock" meaning in English

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  "lang_code": "en",
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          "langcode": "en",
          "name": "Musical genres",
          "orig": "en:Musical genres",
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          "ref": "2016 July 7, Alexis Petridis, “Roísín Murphy: Take Her Up to Monto review – still too strange for the bigtime”, in The Guardian",
          "text": "Its opening track, Mastermind, offers one possible answer to a theoretical question about what prog rock might have sounded like in the highly unlikely event that it had co-opted Giorgio Moroder’s brand of electronic disco: […]",
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        "Clipping of progressive rock."
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        "(music) Clipping of progressive rock."
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  "word": "prog rock"
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  "lang_code": "en",
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        "en:Musical genres"
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          "text": "Its opening track, Mastermind, offers one possible answer to a theoretical question about what prog rock might have sounded like in the highly unlikely event that it had co-opted Giorgio Moroder’s brand of electronic disco: […]",
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        "(music) Clipping of progressive rock."
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  "word": "prog rock"
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