"serial comma" meaning in English

{
  "forms": [
    {
      "form": "serial commas",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "serial comma (plural serial commas)",
      "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"
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          "source": "w"
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          "parents": [],
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        },
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          "kind": "other",
          "name": "Mandarin terms with redundant transliterations",
          "parents": [
            "Terms with redundant transliterations",
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          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
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          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Dutch translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Finnish translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Mandarin translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Terms with Swedish translations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Punctuation marks",
          "orig": "en:Punctuation marks",
          "parents": [
            "Letters, symbols, and punctuation",
            "Symbols",
            "Orthography",
            "Writing",
            "Human behaviour",
            "Language",
            "Human",
            "Communication",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "A comma preceding the final conjunction in a list of three or more items, especially to provide clarity."
      ],
      "id": "en-serial_comma-en-noun-IlcB9Bn~",
      "links": [
        [
          "conjunction",
          "conjunction"
        ],
        [
          "list",
          "list"
        ],
        [
          "item",
          "item"
        ],
        [
          "clarity",
          "clarity"
        ]
      ],
      "synonyms": [
        {
          "english": "UK & US",
          "word": "Oxford comma"
        },
        {
          "tags": [
            "US"
          ],
          "word": "Harvard comma"
        }
      ],
      "translations": [
        {
          "code": "cmn",
          "lang": "Chinese Mandarin",
          "sense": "comma preceding the final conjunction in a list",
          "word": "連續逗號"
        },
        {
          "code": "cmn",
          "lang": "Chinese Mandarin",
          "roman": "liánxù dòuhào",
          "sense": "comma preceding the final conjunction in a list",
          "word": "连续逗号"
        },
        {
          "code": "cmn",
          "lang": "Chinese Mandarin",
          "sense": "comma preceding the final conjunction in a list",
          "word": "牛津逗號"
        },
        {
          "code": "cmn",
          "lang": "Chinese Mandarin",
          "roman": "Niújīn dòuhào",
          "sense": "comma preceding the final conjunction in a list",
          "word": "牛津逗号"
        },
        {
          "code": "cmn",
          "lang": "Chinese Mandarin",
          "sense": "comma preceding the final conjunction in a list",
          "word": "哈佛逗號"
        },
        {
          "code": "cmn",
          "lang": "Chinese Mandarin",
          "roman": "Hāfó dòuhào",
          "sense": "comma preceding the final conjunction in a list",
          "word": "哈佛逗号"
        },
        {
          "code": "nl",
          "lang": "Dutch",
          "sense": "comma preceding the final conjunction in a list",
          "word": "Oxford-komma"
        },
        {
          "code": "fi",
          "lang": "Finnish",
          "sense": "comma preceding the final conjunction in a list",
          "word": "Oxford-pilkku"
        },
        {
          "code": "sv",
          "lang": "Swedish",
          "sense": "comma preceding the final conjunction in a list",
          "word": "Oxfordkomma"
        },
        {
          "code": "sv",
          "lang": "Swedish",
          "sense": "comma preceding the final conjunction in a list",
          "word": "Oxford-komma"
        }
      ]
    }
  ],
  "sounds": [
    {
      "audio": "En-us-serial comma.oga",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/b/b8/En-us-serial_comma.oga/En-us-serial_comma.oga.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/b/b8/En-us-serial_comma.oga"
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  ],
  "word": "serial comma"
}

{
  "forms": [
    {
      "form": "serial commas",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "serial comma (plural serial commas)",
      "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",
        "Entries with translation boxes",
        "Mandarin terms with redundant transliterations",
        "Pages with 1 entry",
        "Pages with entries",
        "Terms with Dutch translations",
        "Terms with Finnish translations",
        "Terms with Mandarin translations",
        "Terms with Swedish translations",
        "en:Punctuation marks"
      ],
      "glosses": [
        "A comma preceding the final conjunction in a list of three or more items, especially to provide clarity."
      ],
      "links": [
        [
          "conjunction",
          "conjunction"
        ],
        [
          "list",
          "list"
        ],
        [
          "item",
          "item"
        ],
        [
          "clarity",
          "clarity"
        ]
      ],
      "synonyms": [
        {
          "english": "UK & US",
          "word": "Oxford comma"
        },
        {
          "tags": [
            "US"
          ],
          "word": "Harvard comma"
        }
      ]
    }
  ],
  "sounds": [
    {
      "audio": "En-us-serial comma.oga",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/b/b8/En-us-serial_comma.oga/En-us-serial_comma.oga.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/b/b8/En-us-serial_comma.oga"
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  ],
  "translations": [
    {
      "code": "cmn",
      "lang": "Chinese Mandarin",
      "sense": "comma preceding the final conjunction in a list",
      "word": "連續逗號"
    },
    {
      "code": "cmn",
      "lang": "Chinese Mandarin",
      "roman": "liánxù dòuhào",
      "sense": "comma preceding the final conjunction in a list",
      "word": "连续逗号"
    },
    {
      "code": "cmn",
      "lang": "Chinese Mandarin",
      "sense": "comma preceding the final conjunction in a list",
      "word": "牛津逗號"
    },
    {
      "code": "cmn",
      "lang": "Chinese Mandarin",
      "roman": "Niújīn dòuhào",
      "sense": "comma preceding the final conjunction in a list",
      "word": "牛津逗号"
    },
    {
      "code": "cmn",
      "lang": "Chinese Mandarin",
      "sense": "comma preceding the final conjunction in a list",
      "word": "哈佛逗號"
    },
    {
      "code": "cmn",
      "lang": "Chinese Mandarin",
      "roman": "Hāfó dòuhào",
      "sense": "comma preceding the final conjunction in a list",
      "word": "哈佛逗号"
    },
    {
      "code": "nl",
      "lang": "Dutch",
      "sense": "comma preceding the final conjunction in a list",
      "word": "Oxford-komma"
    },
    {
      "code": "fi",
      "lang": "Finnish",
      "sense": "comma preceding the final conjunction in a list",
      "word": "Oxford-pilkku"
    },
    {
      "code": "sv",
      "lang": "Swedish",
      "sense": "comma preceding the final conjunction in a list",
      "word": "Oxfordkomma"
    },
    {
      "code": "sv",
      "lang": "Swedish",
      "sense": "comma preceding the final conjunction in a list",
      "word": "Oxford-komma"
    }
  ],
  "word": "serial comma"
}