"SUN" meaning in Conventions internationales

{
  "categories": [
    {
      "kind": "other",
      "name": "Symboles en conventions internationales",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Conventions internationales",
      "orig": "conventions internationales",
      "parents": [],
      "source": "w"
    }
  ],
  "lang": "Conventions internationales",
  "lang_code": "conv",
  "pos": "symbol",
  "pos_title": "Symbole",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Termes désuets en conventions internationales",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "Union soviétique (norme ISO 3166-1 alpha-3) en vigueur 1974–1992, fractionné en ARM, AZE, EST, GEO, KAZ, KGZ, LVA, LTU, MDA, RUS, TJK, TKM et UZB."
      ],
      "id": "fr-SUN-conv-symbol-YXY-nf5J",
      "tags": [
        "obsolete"
      ]
    }
  ],
  "tags": [
    "invariable"
  ],
  "word": "SUN"
}

{
  "categories": [
    "Symboles en conventions internationales",
    "conventions internationales"
  ],
  "lang": "Conventions internationales",
  "lang_code": "conv",
  "pos": "symbol",
  "pos_title": "Symbole",
  "senses": [
    {
      "categories": [
        "Termes désuets en conventions internationales"
      ],
      "glosses": [
        "Union soviétique (norme ISO 3166-1 alpha-3) en vigueur 1974–1992, fractionné en ARM, AZE, EST, GEO, KAZ, KGZ, LVA, LTU, MDA, RUS, TJK, TKM et UZB."
      ],
      "tags": [
        "obsolete"
      ]
    }
  ],
  "tags": [
    "invariable"
  ],
  "word": "SUN"
}