"prima tercera" meaning in Spanish

{
  "forms": [
    {
      "form": "primas terceras",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "f"
      },
      "expansion": "prima tercera f (plural primas terceras)",
      "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": "topical",
          "langcode": "es",
          "name": "Family members",
          "orig": "es:Family members",
          "parents": [
            "Family",
            "People",
            "Human",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "coordinate_terms": [
        {
          "word": "prima cuarta"
        },
        {
          "word": "prima hermana"
        },
        {
          "word": "prima quinta"
        },
        {
          "word": "prima segunda"
        }
      ],
      "form_of": [
        {
          "extra": "third cousin",
          "word": "primo tercero"
        }
      ],
      "glosses": [
        "female equivalent of primo tercero (“third cousin”)"
      ],
      "id": "en-prima_tercera-es-noun-LlII5o~K",
      "links": [
        [
          "primo tercero",
          "primo tercero#Spanish"
        ]
      ],
      "tags": [
        "feminine",
        "form-of"
      ],
      "wikipedia": [
        "es:primo tercero"
      ]
    }
  ],
  "word": "prima tercera"
}

{
  "coordinate_terms": [
    {
      "word": "prima cuarta"
    },
    {
      "word": "prima hermana"
    },
    {
      "word": "prima quinta"
    },
    {
      "word": "prima segunda"
    }
  ],
  "forms": [
    {
      "form": "primas terceras",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "f"
      },
      "expansion": "prima tercera f (plural primas terceras)",
      "name": "es-noun"
    }
  ],
  "lang": "Spanish",
  "lang_code": "es",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "Spanish countable nouns",
        "Spanish entries with incorrect language header",
        "Spanish female equivalent nouns",
        "Spanish feminine nouns",
        "Spanish lemmas",
        "Spanish multiword terms",
        "Spanish nouns",
        "Spanish nouns with red links in their headword lines",
        "es:Family members"
      ],
      "form_of": [
        {
          "extra": "third cousin",
          "word": "primo tercero"
        }
      ],
      "glosses": [
        "female equivalent of primo tercero (“third cousin”)"
      ],
      "links": [
        [
          "primo tercero",
          "primo tercero#Spanish"
        ]
      ],
      "tags": [
        "feminine",
        "form-of"
      ],
      "wikipedia": [
        "es:primo tercero"
      ]
    }
  ],
  "word": "prima tercera"
}