"рѣдко" meaning in Russian

{
  "forms": [
    {
      "form": "рѣ́дко",
      "tags": [
        "canonical"
      ]
    },
    {
      "form": "rě́dko",
      "tags": [
        "romanization"
      ]
    },
    {
      "form": "(по)рѣ́же",
      "tags": [
        "comparative"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "рѣ́дко",
        "2": "рѣ́же"
      },
      "expansion": "рѣ́дко • (rě́dko) (comparative (по)рѣ́же)",
      "name": "ru-adv"
    }
  ],
  "lang": "Russian",
  "lang_code": "ru",
  "pos": "adv",
  "senses": [
    {
      "alt_of": [
        {
          "extra": "rédko",
          "word": "ре́дко"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "Russian entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Russian pre-1918 spellings",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "Pre-1918 spelling of ре́дко (rédko)."
      ],
      "id": "en-рѣдко-ru-adv-U8dg2NLF",
      "links": [
        [
          "ре́дко",
          "редко#Russian"
        ]
      ],
      "tags": [
        "alt-of",
        "dated"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "[ˈrʲetkə]"
    }
  ],
  "word": "рѣдко"
}

{
  "forms": [
    {
      "form": "рѣ́дко",
      "tags": [
        "canonical"
      ]
    },
    {
      "form": "rě́dko",
      "tags": [
        "romanization"
      ]
    },
    {
      "form": "(по)рѣ́же",
      "tags": [
        "comparative"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "рѣ́дко",
        "2": "рѣ́же"
      },
      "expansion": "рѣ́дко • (rě́dko) (comparative (по)рѣ́же)",
      "name": "ru-adv"
    }
  ],
  "lang": "Russian",
  "lang_code": "ru",
  "pos": "adv",
  "senses": [
    {
      "alt_of": [
        {
          "extra": "rédko",
          "word": "ре́дко"
        }
      ],
      "categories": [
        "Russian 2-syllable words",
        "Russian adverbs",
        "Russian entries with incorrect language header",
        "Russian lemmas",
        "Russian obsolete forms",
        "Russian pre-1918 spellings",
        "Russian terms spelled with Ѣ",
        "Russian terms with IPA pronunciation"
      ],
      "glosses": [
        "Pre-1918 spelling of ре́дко (rédko)."
      ],
      "links": [
        [
          "ре́дко",
          "редко#Russian"
        ]
      ],
      "tags": [
        "alt-of",
        "dated"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "[ˈrʲetkə]"
    }
  ],
  "word": "рѣдко"
}