"sleeper shark" meaning in English

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  "etymology_text": "From sleeper + shark, referring to their slow, lethargic habits.",
  "forms": [
    {
      "form": "sleeper sharks",
      "tags": [
        "plural"
      ]
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      "expansion": "sleeper shark (plural sleeper sharks)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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        {
          "kind": "lifeform",
          "langcode": "en",
          "name": "Sharks",
          "orig": "en:Sharks",
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      "glosses": [
        "Any shark of the family Somniosidae."
      ],
      "id": "en-sleeper_shark-en-noun-4lSOLRZg",
      "links": [
        [
          "shark",
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      "synonyms": [
        {
          "word": "sleepershark"
        }
      ]
    }
  ],
  "word": "sleeper shark"
}

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  ],
  "etymology_text": "From sleeper + shark, referring to their slow, lethargic habits.",
  "forms": [
    {
      "form": "sleeper sharks",
      "tags": [
        "plural"
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  "lang_code": "en",
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        "Any shark of the family Somniosidae."
      ],
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  "synonyms": [
    {
      "word": "sleepershark"
    }
  ],
  "word": "sleeper shark"
}