"dumb hole" meaning in English

{
  "etymology_text": "Similar to black hole, formed with dumb (“mute, silent”). Used at least since 1994.",
  "forms": [
    {
      "form": "dumb holes",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "dumb hole (plural dumb holes)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Black holes",
          "orig": "en:Black holes",
          "parents": [
            "Astronomy",
            "Astrophysics",
            "Gravity",
            "Relativity",
            "Sciences",
            "Space",
            "Physics",
            "Acceleration",
            "Mechanics",
            "All topics",
            "Nature",
            "Fundamental"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Physics",
          "orig": "en:Physics",
          "parents": [
            "Sciences",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "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."
      ],
      "id": "en-dumb_hole-en-noun-WQsKAo2S",
      "links": [
        [
          "phonon",
          "phonon"
        ],
        [
          "fluid",
          "fluid"
        ],
        [
          "speed of sound",
          "speed of sound"
        ]
      ],
      "synonyms": [
        {
          "word": "sonic black hole"
        }
      ],
      "wikipedia": [
        "dumb hole"
      ]
    }
  ],
  "word": "dumb hole"
}

{
  "etymology_text": "Similar to black hole, formed with dumb (“mute, silent”). Used at least since 1994.",
  "forms": [
    {
      "form": "dumb holes",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "dumb hole (plural dumb holes)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "Pages with 1 entry",
        "Pages with entries",
        "en:Black holes",
        "en:Physics"
      ],
      "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."
      ],
      "links": [
        [
          "phonon",
          "phonon"
        ],
        [
          "fluid",
          "fluid"
        ],
        [
          "speed of sound",
          "speed of sound"
        ]
      ],
      "wikipedia": [
        "dumb hole"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "sonic black hole"
    }
  ],
  "word": "dumb hole"
}