"FF. AA." meaning in Spanish

{
  "etymology_templates": [
    {
      "args": {
        "1": "es",
        "2": "fuerzas armadas"
      },
      "expansion": "Initialism of fuerzas armadas",
      "name": "initialism"
    }
  ],
  "etymology_text": "Initialism of fuerzas armadas.",
  "head_templates": [
    {
      "args": {
        "1": "f-p",
        "head": "FF. AA."
      },
      "expansion": "FF. AA. f pl (plural only)",
      "name": "es-noun"
    }
  ],
  "lang": "Spanish",
  "lang_code": "es",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Spanish entries with incorrect language header",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Spanish links with redundant alt parameters",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Spanish links with redundant wikilinks",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Spanish pluralia tantum",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "armed forces"
      ],
      "id": "en-FF._AA.-es-noun-Gi-6~vN7",
      "links": [
        [
          "armed forces",
          "armed forces"
        ]
      ],
      "tags": [
        "feminine",
        "plural",
        "plural-only"
      ]
    }
  ],
  "word": "FF. AA."
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "es",
        "2": "fuerzas armadas"
      },
      "expansion": "Initialism of fuerzas armadas",
      "name": "initialism"
    }
  ],
  "etymology_text": "Initialism of fuerzas armadas.",
  "head_templates": [
    {
      "args": {
        "1": "f-p",
        "head": "FF. AA."
      },
      "expansion": "FF. AA. f pl (plural only)",
      "name": "es-noun"
    }
  ],
  "lang": "Spanish",
  "lang_code": "es",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "Pages with 1 entry",
        "Pages with entries",
        "Spanish entries with incorrect language header",
        "Spanish feminine nouns",
        "Spanish initialisms",
        "Spanish lemmas",
        "Spanish links with redundant alt parameters",
        "Spanish links with redundant wikilinks",
        "Spanish multiword terms",
        "Spanish nouns",
        "Spanish pluralia tantum",
        "Spanish terms spelled with ."
      ],
      "glosses": [
        "armed forces"
      ],
      "links": [
        [
          "armed forces",
          "armed forces"
        ]
      ],
      "tags": [
        "feminine",
        "plural",
        "plural-only"
      ]
    }
  ],
  "word": "FF. AA."
}