"ЧК" meaning in Russian

{
  "etymology_templates": [
    {
      "args": {
        "1": "ru",
        "2": "Чрезвыча́йная коми́ссия"
      },
      "expansion": "Initialism of Чрезвыча́йная коми́ссия (Črezvyčájnaja komíssija)",
      "name": "initialism"
    }
  ],
  "etymology_text": "Initialism of Чрезвыча́йная коми́ссия (Črezvyčájnaja komíssija), short for Всеросси́йская чрезвыча́йная коми́ссия (Vserossíjskaja črezvyčájnaja komíssija, “All-Russian Extraordinary Commission”).",
  "forms": [
    {
      "form": "ČK",
      "tags": [
        "romanization"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "",
        "2": "f-in",
        "3": "-"
      },
      "expansion": "ЧК • (ČK) f inan (indeclinable)",
      "name": "ru-proper noun"
    }
  ],
  "lang": "Russian",
  "lang_code": "ru",
  "pos": "name",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Russian entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "derived": [
        {
          "roman": "Čeká",
          "word": "Чека́"
        },
        {
          "roman": "čekíst",
          "word": "чеки́ст"
        }
      ],
      "glosses": [
        "Cheka (forerunner of the KGB)"
      ],
      "id": "en-ЧК-ru-name--yMTsFtb",
      "links": [
        [
          "Cheka",
          "Cheka"
        ],
        [
          "KGB",
          "KGB"
        ]
      ],
      "related": [
        {
          "roman": "KGB",
          "word": "КГБ"
        },
        {
          "roman": "FSB",
          "word": "ФСБ"
        }
      ],
      "synonyms": [
        {
          "word": "ВЧК"
        }
      ],
      "tags": [
        "indeclinable"
      ],
      "wikipedia": [
        "Cheka"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "[t͡ɕe ˈka]"
    }
  ],
  "word": "ЧК"
}

{
  "derived": [
    {
      "roman": "Čeká",
      "word": "Чека́"
    },
    {
      "roman": "čekíst",
      "word": "чеки́ст"
    }
  ],
  "etymology_templates": [
    {
      "args": {
        "1": "ru",
        "2": "Чрезвыча́йная коми́ссия"
      },
      "expansion": "Initialism of Чрезвыча́йная коми́ссия (Črezvyčájnaja komíssija)",
      "name": "initialism"
    }
  ],
  "etymology_text": "Initialism of Чрезвыча́йная коми́ссия (Črezvyčájnaja komíssija), short for Всеросси́йская чрезвыча́йная коми́ссия (Vserossíjskaja črezvyčájnaja komíssija, “All-Russian Extraordinary Commission”).",
  "forms": [
    {
      "form": "ČK",
      "tags": [
        "romanization"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "",
        "2": "f-in",
        "3": "-"
      },
      "expansion": "ЧК • (ČK) f inan (indeclinable)",
      "name": "ru-proper noun"
    }
  ],
  "lang": "Russian",
  "lang_code": "ru",
  "pos": "name",
  "related": [
    {
      "roman": "KGB",
      "word": "КГБ"
    },
    {
      "roman": "FSB",
      "word": "ФСБ"
    }
  ],
  "senses": [
    {
      "categories": [
        "Pages with 1 entry",
        "Pages with entries",
        "Russian entries with incorrect language header",
        "Russian feminine nouns",
        "Russian inanimate nouns",
        "Russian indeclinable nouns",
        "Russian initialisms",
        "Russian lemmas",
        "Russian proper nouns",
        "Russian terms with IPA pronunciation",
        "Russian terms with redundant head parameter"
      ],
      "glosses": [
        "Cheka (forerunner of the KGB)"
      ],
      "links": [
        [
          "Cheka",
          "Cheka"
        ],
        [
          "KGB",
          "KGB"
        ]
      ],
      "synonyms": [
        {
          "word": "ВЧК"
        }
      ],
      "tags": [
        "indeclinable"
      ],
      "wikipedia": [
        "Cheka"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "[t͡ɕe ˈka]"
    }
  ],
  "word": "ЧК"
}