"dans le meilleur des cas" meaning in Français

{
  "categories": [
    {
      "kind": "other",
      "name": "Compositions en français",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Locutions adverbiales en français",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Français",
      "orig": "français",
      "parents": [],
      "source": "w"
    }
  ],
  "etymology_texts": [
    "Composé de dans, meilleur et cas."
  ],
  "lang": "Français",
  "lang_code": "fr",
  "pos": "adv",
  "pos_title": "Locution adverbiale",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Exemples en français",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "text": "Idéalement"
        }
      ],
      "glosses": [
        "Dans des conditions optimales, au mieux."
      ],
      "id": "fr-dans_le_meilleur_des_cas-fr-adv-JPF4RzVj"
    }
  ],
  "sounds": [
    {
      "ipa": "\\dɑ̃ lə mɛ.jœʁ de ka\\"
    }
  ],
  "word": "dans le meilleur des cas"
}

{
  "categories": [
    "Compositions en français",
    "Locutions adverbiales en français",
    "français"
  ],
  "etymology_texts": [
    "Composé de dans, meilleur et cas."
  ],
  "lang": "Français",
  "lang_code": "fr",
  "pos": "adv",
  "pos_title": "Locution adverbiale",
  "senses": [
    {
      "categories": [
        "Exemples en français"
      ],
      "examples": [
        {
          "text": "Idéalement"
        }
      ],
      "glosses": [
        "Dans des conditions optimales, au mieux."
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "\\dɑ̃ lə mɛ.jœʁ de ka\\"
    }
  ],
  "word": "dans le meilleur des cas"
}