"fake book" meaning in English

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "fake",
        "3": "book",
        "pos1": "verb"
      },
      "expansion": "fake (verb) + book",
      "name": "compound"
    }
  ],
  "etymology_text": "From fake (verb) + book: a fake book helps a musician to \"fake\" knowing how to play a song.",
  "forms": [
    {
      "form": "fake books",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "fake book (plural fake books)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Music",
          "orig": "en:Music",
          "parents": [
            "Art",
            "Sound",
            "Culture",
            "Energy",
            "Society",
            "Nature",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        },
        {
          "_dis": "93 7",
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w+disamb"
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        {
          "_dis": "90 10",
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          "parents": [],
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        },
        {
          "_dis": "77 23",
          "kind": "other",
          "name": "Terms with Finnish translations",
          "parents": [],
          "source": "w+disamb"
        },
        {
          "_dis": "76 24",
          "kind": "other",
          "name": "Terms with Mandarin translations",
          "parents": [],
          "source": "w+disamb"
        }
      ],
      "glosses": [
        "A collection of musical lead sheets intended to help a performer quickly learn new songs."
      ],
      "id": "en-fake_book-en-noun-YrVQygaP",
      "links": [
        [
          "music",
          "music"
        ],
        [
          "collection",
          "collection"
        ],
        [
          "musical",
          "musical"
        ],
        [
          "lead sheets",
          "lead sheet"
        ],
        [
          "performer",
          "performer"
        ],
        [
          "song",
          "song"
        ]
      ],
      "raw_glosses": [
        "(music) A collection of musical lead sheets intended to help a performer quickly learn new songs."
      ],
      "topics": [
        "entertainment",
        "lifestyle",
        "music"
      ],
      "translations": [
        {
          "_dis1": "99 1",
          "code": "cmn",
          "lang": "Chinese Mandarin",
          "roman": "gēqǔjí",
          "sense": "collection of musical lead sheets",
          "word": "歌曲集"
        },
        {
          "_dis1": "99 1",
          "code": "fi",
          "lang": "Finnish",
          "sense": "collection of musical lead sheets",
          "word": "fake book"
        }
      ]
    },
    {
      "glosses": [
        "Used other than figuratively or idiomatically: see fake, book."
      ],
      "id": "en-fake_book-en-noun-7hDJHEMb",
      "links": [
        [
          "fake",
          "fake#English"
        ],
        [
          "book",
          "book#English"
        ]
      ],
      "synonyms": [
        {
          "_dis1": "0 100",
          "word": "fakebook"
        }
      ]
    }
  ],
  "wikipedia": [
    "fake book"
  ],
  "word": "fake book"
}

{
  "categories": [
    "English adjective-noun compound nouns",
    "English compound terms",
    "English countable nouns",
    "English entries with incorrect language header",
    "English lemmas",
    "English multiword terms",
    "English nouns",
    "Entries with translation boxes",
    "Pages with 1 entry",
    "Pages with entries",
    "Terms with Finnish translations",
    "Terms with Mandarin translations"
  ],
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "fake",
        "3": "book",
        "pos1": "verb"
      },
      "expansion": "fake (verb) + book",
      "name": "compound"
    }
  ],
  "etymology_text": "From fake (verb) + book: a fake book helps a musician to \"fake\" knowing how to play a song.",
  "forms": [
    {
      "form": "fake books",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "fake book (plural fake books)",
      "name": "en-noun"
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "en:Music"
      ],
      "glosses": [
        "A collection of musical lead sheets intended to help a performer quickly learn new songs."
      ],
      "links": [
        [
          "music",
          "music"
        ],
        [
          "collection",
          "collection"
        ],
        [
          "musical",
          "musical"
        ],
        [
          "lead sheets",
          "lead sheet"
        ],
        [
          "performer",
          "performer"
        ],
        [
          "song",
          "song"
        ]
      ],
      "raw_glosses": [
        "(music) A collection of musical lead sheets intended to help a performer quickly learn new songs."
      ],
      "topics": [
        "entertainment",
        "lifestyle",
        "music"
      ]
    },
    {
      "glosses": [
        "Used other than figuratively or idiomatically: see fake, book."
      ],
      "links": [
        [
          "fake",
          "fake#English"
        ],
        [
          "book",
          "book#English"
        ]
      ]
    }
  ],
  "synonyms": [
    {
      "word": "fakebook"
    }
  ],
  "translations": [
    {
      "code": "cmn",
      "lang": "Chinese Mandarin",
      "roman": "gēqǔjí",
      "sense": "collection of musical lead sheets",
      "word": "歌曲集"
    },
    {
      "code": "fi",
      "lang": "Finnish",
      "sense": "collection of musical lead sheets",
      "word": "fake book"
    }
  ],
  "wikipedia": [
    "fake book"
  ],
  "word": "fake book"
}