"idiota útil" meaning in Spanish

{
  "forms": [
    {
      "form": "idiotas útiles",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "mfbysense"
      },
      "expansion": "idiota útil m or f by sense (plural idiotas útiles)",
      "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"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Spanish masculine and feminine nouns by sense",
          "parents": [
            "Masculine and feminine nouns by sense",
            "Nouns by gender",
            "Nouns",
            "Lemmas"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Spanish nouns with irregular gender",
          "parents": [
            "Nouns with irregular gender",
            "Irregular nouns",
            "Nouns by inflection type",
            "Nouns",
            "Lemmas"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "useful idiot"
      ],
      "id": "en-idiota_útil-es-noun-NANmIK~Z",
      "links": [
        [
          "useful idiot",
          "useful idiot"
        ]
      ],
      "tags": [
        "by-personal-gender",
        "feminine",
        "masculine"
      ]
    }
  ],
  "word": "idiota útil"
}

{
  "forms": [
    {
      "form": "idiotas útiles",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "mfbysense"
      },
      "expansion": "idiota útil m or f by sense (plural idiotas útiles)",
      "name": "es-noun"
    }
  ],
  "lang": "Spanish",
  "lang_code": "es",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "Spanish countable nouns",
        "Spanish entries with incorrect language header",
        "Spanish feminine nouns",
        "Spanish lemmas",
        "Spanish masculine and feminine nouns by sense",
        "Spanish masculine nouns",
        "Spanish multiword terms",
        "Spanish nouns",
        "Spanish nouns with irregular gender",
        "Spanish nouns with multiple genders",
        "Spanish nouns with red links in their headword lines"
      ],
      "glosses": [
        "useful idiot"
      ],
      "links": [
        [
          "useful idiot",
          "useful idiot"
        ]
      ],
      "tags": [
        "by-personal-gender",
        "feminine",
        "masculine"
      ]
    }
  ],
  "word": "idiota útil"
}