"HPF" meaning in English

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      "expansion": "HPF (plural HPFs)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
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      "alt_of": [
        {
          "word": "high-pass filter"
        }
      ],
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          "langcode": "en",
          "name": "Signal processing",
          "orig": "en:Signal processing",
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      "glosses": [
        "Initialism of high-pass filter."
      ],
      "id": "en-HPF-en-noun-sQEiFB6V",
      "links": [
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      "raw_glosses": [
        "(signal processing) Initialism of high-pass filter."
      ],
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      "topics": [
        "computing",
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        "natural-sciences",
        "physical-sciences",
        "sciences",
        "signal-processing"
      ]
    }
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  "word": "HPF"
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    {
      "form": "HPFs",
      "tags": [
        "plural"
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    }
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  "head_templates": [
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      "expansion": "HPF (plural HPFs)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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        {
          "word": "high-pass filter"
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      "glosses": [
        "Initialism of high-pass filter."
      ],
      "links": [
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          "high-pass filter",
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      ],
      "raw_glosses": [
        "(signal processing) Initialism of high-pass filter."
      ],
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      "topics": [
        "computing",
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        "signal-processing"
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  ],
  "word": "HPF"
}