"holy grail" meaning in English

{
  "forms": [
    {
      "form": "holy grails",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "holy grail (plural holy grails)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "Holy Grail"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "2011 July 18, John Cassidy, “Mastering the Machine”, in The New Yorker, →ISSN",
          "text": "“Making money on a constant basis is the holy grail, and Ray and Bridgewater have done that,” Ng Kok-Song, the chief investment officer of the Singapore fund, told me.",
          "type": "quotation"
        },
        {
          "ref": "2023 June 10, Phil McNulty, “Manchester City 1 - 0 Inter Milan”, in BBC Sport",
          "text": "For City's owners, with Sheikh Mansour attending only his second game since taking control in 2008, this was the night they have planned for and the one when they finally claimed that holy grail.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Alternative letter-case form of Holy Grail"
      ],
      "id": "en-holy_grail-en-noun-2bHnGdU3",
      "links": [
        [
          "Holy Grail",
          "Holy Grail#English"
        ]
      ],
      "tags": [
        "alt-of"
      ]
    }
  ],
  "word": "holy grail"
}

{
  "forms": [
    {
      "form": "holy grails",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "holy grail (plural holy grails)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "Holy Grail"
        }
      ],
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms with quotations"
      ],
      "examples": [
        {
          "ref": "2011 July 18, John Cassidy, “Mastering the Machine”, in The New Yorker, →ISSN",
          "text": "“Making money on a constant basis is the holy grail, and Ray and Bridgewater have done that,” Ng Kok-Song, the chief investment officer of the Singapore fund, told me.",
          "type": "quotation"
        },
        {
          "ref": "2023 June 10, Phil McNulty, “Manchester City 1 - 0 Inter Milan”, in BBC Sport",
          "text": "For City's owners, with Sheikh Mansour attending only his second game since taking control in 2008, this was the night they have planned for and the one when they finally claimed that holy grail.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Alternative letter-case form of Holy Grail"
      ],
      "links": [
        [
          "Holy Grail",
          "Holy Grail#English"
        ]
      ],
      "tags": [
        "alt-of"
      ]
    }
  ],
  "word": "holy grail"
}