"big bad" meaning in English

{
  "etymology_text": "First coined in 1998 in the episode Bewitched, Bothered and Bewildered, season two of Buffy the Vampire Slayer.",
  "forms": [
    {
      "form": "big bads",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "big bad (plural big bads)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English alliterative compounds",
          "parents": [
            "Alliterative compounds",
            "Alliterative phrases",
            "Compound terms",
            "Phrases",
            "Terms by etymology",
            "Lemmas",
            "Multiword terms"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with language name categories using raw markup",
          "parents": [
            "Entries with language name categories using raw markup",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with topic categories using raw markup",
          "parents": [
            "Entries with topic categories using raw markup",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English terms with non-redundant non-automated sortkeys",
          "parents": [
            "Terms with non-redundant non-automated sortkeys",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Fiction",
          "orig": "en:Fiction",
          "parents": [
            "Artistic works",
            "Art",
            "Culture",
            "Society",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "2017 September 19, Gwilym Mumford, “Kingsman: The Golden Circle review – spy sequel reaches new heights of skyscraping silliness”, in the Guardian",
          "text": "Charlie, now menacingly equipped with a bionic arm, is these days in the service of new pantomime big bad, Poppy Adams, played with lysergic glee by Julianne Moore.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A major adversary or antagonist of a piece of fiction."
      ],
      "id": "en-big_bad-en-noun-YQ1dETuV",
      "links": [
        [
          "adversary",
          "adversary"
        ],
        [
          "antagonist",
          "antagonist"
        ]
      ]
    }
  ],
  "word": "big bad"
}

{
  "etymology_text": "First coined in 1998 in the episode Bewitched, Bothered and Bewildered, season two of Buffy the Vampire Slayer.",
  "forms": [
    {
      "form": "big bads",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "big bad (plural big bads)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "English alliterative compounds",
        "English countable nouns",
        "English entries with incorrect language header",
        "English entries with language name categories using raw markup",
        "English entries with topic categories using raw markup",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms with non-redundant non-automated sortkeys",
        "English terms with quotations",
        "en:Fiction"
      ],
      "examples": [
        {
          "ref": "2017 September 19, Gwilym Mumford, “Kingsman: The Golden Circle review – spy sequel reaches new heights of skyscraping silliness”, in the Guardian",
          "text": "Charlie, now menacingly equipped with a bionic arm, is these days in the service of new pantomime big bad, Poppy Adams, played with lysergic glee by Julianne Moore.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A major adversary or antagonist of a piece of fiction."
      ],
      "links": [
        [
          "adversary",
          "adversary"
        ],
        [
          "antagonist",
          "antagonist"
        ]
      ]
    }
  ],
  "word": "big bad"
}