"upsilon" meaning in French

{
  "etymology_templates": [
    {
      "args": {
        "1": "fr",
        "2": "grc",
        "3": "ὖ ψιλόν",
        "4": ""
      },
      "expansion": "Ancient Greek ὖ ψιλόν (û psilón)",
      "name": "uder"
    }
  ],
  "etymology_text": "From Ancient Greek ὖ ψιλόν (û psilón).",
  "head_templates": [
    {
      "args": {
        "1": "m",
        "2": "#"
      },
      "expansion": "upsilon m (invariable)",
      "name": "fr-noun"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "French entries with incorrect language header",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "French undefined derivations",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 3 entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "langcode": "fr",
          "name": "Greek letter names",
          "orig": "fr:Greek letter names",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "upsilon (Greek letter)"
      ],
      "id": "en-upsilon-fr-noun-r9ilxVWG",
      "links": [
        [
          "upsilon",
          "upsilon#English"
        ]
      ],
      "synonyms": [
        {
          "word": "i grec"
        }
      ],
      "tags": [
        "invariable",
        "masculine"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/yp.si.lɔ̃/"
    },
    {
      "ipa": "/yp.si.lɔn/"
    }
  ],
  "word": "upsilon"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "fr",
        "2": "grc",
        "3": "ὖ ψιλόν",
        "4": ""
      },
      "expansion": "Ancient Greek ὖ ψιλόν (û psilón)",
      "name": "uder"
    }
  ],
  "etymology_text": "From Ancient Greek ὖ ψιλόν (û psilón).",
  "head_templates": [
    {
      "args": {
        "1": "m",
        "2": "#"
      },
      "expansion": "upsilon m (invariable)",
      "name": "fr-noun"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "French 3-syllable words",
        "French countable nouns",
        "French entries with incorrect language header",
        "French indeclinable nouns",
        "French lemmas",
        "French masculine nouns",
        "French nouns",
        "French terms derived from Ancient Greek",
        "French terms with IPA pronunciation",
        "French undefined derivations",
        "Pages with 3 entries",
        "Pages with entries",
        "fr:Greek letter names"
      ],
      "glosses": [
        "upsilon (Greek letter)"
      ],
      "links": [
        [
          "upsilon",
          "upsilon#English"
        ]
      ],
      "synonyms": [
        {
          "word": "i grec"
        }
      ],
      "tags": [
        "invariable",
        "masculine"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/yp.si.lɔ̃/"
    },
    {
      "ipa": "/yp.si.lɔn/"
    }
  ],
  "word": "upsilon"
}