"in the sack" meaning in English

{
  "head_templates": [
    {
      "args": {
        "1": "en",
        "2": "prepositional phrase",
        "head": ""
      },
      "expansion": "in the sack",
      "name": "head"
    },
    {
      "args": {},
      "expansion": "in the sack",
      "name": "en-prep phrase"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "prep_phrase",
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          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
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        {
          "kind": "topical",
          "langcode": "en",
          "name": "Sex",
          "orig": "en:Sex",
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            "Reproduction",
            "Fundamental",
            "Life",
            "Nature"
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          "kind": "topical",
          "langcode": "en",
          "name": "Sleep",
          "orig": "en:Sleep",
          "parents": [
            "Body",
            "Human",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "text": "I'm pooped—I'll be in the sack if anyone needs me.",
          "type": "example"
        },
        {
          "text": "Her girlfriend was amazing in the sack.",
          "type": "example"
        },
        {
          "ref": "1976, Paddy Chayefsky, Network, spoken by Diana Christensen (Faye Dunaway)",
          "text": "I'm sorry for all those things I said to you last night. You're not the worst fuck I ever had. Believe me, I've had worse. You don't puff or snorkel and make death-like rattles. As a matter of fact, you're rather serene in the sack.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "In bed (either literally or figuratively), especially with reference to sexual intercourse."
      ],
      "id": "en-in_the_sack-en-prep_phrase-FGS5nK4S",
      "links": [
        [
          "In bed",
          "in bed"
        ],
        [
          "literally",
          "literally"
        ],
        [
          "figuratively",
          "figuratively"
        ],
        [
          "sexual intercourse",
          "sexual intercourse"
        ]
      ],
      "raw_glosses": [
        "(idiomatic, slang) In bed (either literally or figuratively), especially with reference to sexual intercourse."
      ],
      "synonyms": [
        {
          "word": "between the sheets"
        },
        {
          "word": "in bed"
        }
      ],
      "tags": [
        "idiomatic",
        "slang"
      ]
    }
  ],
  "word": "in the sack"
}

{
  "head_templates": [
    {
      "args": {
        "1": "en",
        "2": "prepositional phrase",
        "head": ""
      },
      "expansion": "in the sack",
      "name": "head"
    },
    {
      "args": {},
      "expansion": "in the sack",
      "name": "en-prep phrase"
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  "lang": "English",
  "lang_code": "en",
  "pos": "prep_phrase",
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        "en:Sex",
        "en:Sleep"
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      "examples": [
        {
          "text": "I'm pooped—I'll be in the sack if anyone needs me.",
          "type": "example"
        },
        {
          "text": "Her girlfriend was amazing in the sack.",
          "type": "example"
        },
        {
          "ref": "1976, Paddy Chayefsky, Network, spoken by Diana Christensen (Faye Dunaway)",
          "text": "I'm sorry for all those things I said to you last night. You're not the worst fuck I ever had. Believe me, I've had worse. You don't puff or snorkel and make death-like rattles. As a matter of fact, you're rather serene in the sack.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "In bed (either literally or figuratively), especially with reference to sexual intercourse."
      ],
      "links": [
        [
          "In bed",
          "in bed"
        ],
        [
          "literally",
          "literally"
        ],
        [
          "figuratively",
          "figuratively"
        ],
        [
          "sexual intercourse",
          "sexual intercourse"
        ]
      ],
      "raw_glosses": [
        "(idiomatic, slang) In bed (either literally or figuratively), especially with reference to sexual intercourse."
      ],
      "tags": [
        "idiomatic",
        "slang"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "between the sheets"
    },
    {
      "word": "in bed"
    }
  ],
  "word": "in the sack"
}