"dumb hole" meaning in English

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  "etymology_text": "Similar to black hole, formed with dumb (“mute, silent”). Used at least since 1994.",
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  "lang_code": "en",
  "pos": "noun",
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          "name": "Physics",
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      "glosses": [
        "A phenomenon in which phonons (sound perturbations) are unable to escape from a fluid that is flowing more quickly than the local speed of sound."
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        "dumb hole"
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  "word": "dumb hole"
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  "etymology_text": "Similar to black hole, formed with dumb (“mute, silent”). Used at least since 1994.",
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        "A phenomenon in which phonons (sound perturbations) are unable to escape from a fluid that is flowing more quickly than the local speed of sound."
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  "word": "dumb hole"
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