"чему" meaning in Russe

{
  "categories": [
    {
      "kind": "other",
      "name": "Formes de pronoms en russe",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Russe",
      "orig": "russe",
      "parents": [],
      "source": "w"
    }
  ],
  "lang": "Russe",
  "lang_code": "ru",
  "pos": "pron",
  "pos_title": "Forme de pronom",
  "senses": [
    {
      "form_of": [
        {
          "word": "что"
        }
      ],
      "glosses": [
        "Datif de что."
      ],
      "id": "fr-чему-ru-pron-FMp9mGk9"
    }
  ],
  "sounds": [
    {
      "ipa": "\\t͡ɕɪˈmu\\"
    }
  ],
  "tags": [
    "form-of"
  ],
  "word": "чему"
}

{
  "categories": [
    "Formes de pronoms en russe",
    "russe"
  ],
  "lang": "Russe",
  "lang_code": "ru",
  "pos": "pron",
  "pos_title": "Forme de pronom",
  "senses": [
    {
      "form_of": [
        {
          "word": "что"
        }
      ],
      "glosses": [
        "Datif de что."
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "\\t͡ɕɪˈmu\\"
    }
  ],
  "tags": [
    "form-of"
  ],
  "word": "чему"
}