"pies de barro" meaning in Spanish

{
  "head_templates": [
    {
      "args": {
        "1": "m-p"
      },
      "expansion": "pies de barro m pl (plural only)",
      "name": "es-noun"
    }
  ],
  "lang": "Spanish",
  "lang_code": "es",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Spanish entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w"
        },
        {
          "kind": "other",
          "name": "Spanish pluralia tantum",
          "parents": [
            "Pluralia tantum",
            "Nouns",
            "Lemmas"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "english": "(please add an English translation of this quotation)",
          "ref": "2021 February 25, Lluís Pellicer, “La Unión Europea acelera la creación de un “pasaporte sanitario” para salvar la campaña de verano”, in El País",
          "text": "La campaña europea de vacunación arrancó con pies de barro.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "feet of clay"
      ],
      "id": "en-pies_de_barro-es-noun-SQSQ5DNG",
      "links": [
        [
          "feet of clay",
          "feet of clay"
        ]
      ],
      "raw_glosses": [
        "(idiomatic) feet of clay"
      ],
      "tags": [
        "idiomatic",
        "masculine",
        "plural",
        "plural-only"
      ]
    }
  ],
  "word": "pies de barro"
}

{
  "head_templates": [
    {
      "args": {
        "1": "m-p"
      },
      "expansion": "pies de barro m pl (plural only)",
      "name": "es-noun"
    }
  ],
  "lang": "Spanish",
  "lang_code": "es",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "Requests for translations of Spanish quotations",
        "Spanish entries with incorrect language header",
        "Spanish idioms",
        "Spanish lemmas",
        "Spanish masculine nouns",
        "Spanish multiword terms",
        "Spanish nouns",
        "Spanish pluralia tantum",
        "Spanish terms with quotations"
      ],
      "examples": [
        {
          "english": "(please add an English translation of this quotation)",
          "ref": "2021 February 25, Lluís Pellicer, “La Unión Europea acelera la creación de un “pasaporte sanitario” para salvar la campaña de verano”, in El País",
          "text": "La campaña europea de vacunación arrancó con pies de barro.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "feet of clay"
      ],
      "links": [
        [
          "feet of clay",
          "feet of clay"
        ]
      ],
      "raw_glosses": [
        "(idiomatic) feet of clay"
      ],
      "tags": [
        "idiomatic",
        "masculine",
        "plural",
        "plural-only"
      ]
    }
  ],
  "word": "pies de barro"
}