"arachno-" meaning in French

{
  "etymology_templates": [
    {
      "args": {
        "1": "fr",
        "2": "grc",
        "3": "ἀράχνη",
        "t": "spider"
      },
      "expansion": "Ancient Greek ἀράχνη (arákhnē, “spider”)",
      "name": "der"
    }
  ],
  "etymology_text": "From Ancient Greek ἀράχνη (arákhnē, “spider”).",
  "head_templates": [
    {
      "args": {
        "1": "fr",
        "2": "prefix"
      },
      "expansion": "arachno-",
      "name": "head"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "prefix",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "French entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages using catfix",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 3 entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        }
      ],
      "glosses": [
        "arachno-"
      ],
      "id": "en-arachno--fr-prefix-1niaK0zq",
      "links": [
        [
          "arachno-",
          "arachno-#English"
        ]
      ],
      "synonyms": [
        {
          "word": "aranéo-"
        }
      ],
      "tags": [
        "morpheme"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/a.ʁak.no/"
    }
  ],
  "word": "arachno-"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "fr",
        "2": "grc",
        "3": "ἀράχνη",
        "t": "spider"
      },
      "expansion": "Ancient Greek ἀράχνη (arákhnē, “spider”)",
      "name": "der"
    }
  ],
  "etymology_text": "From Ancient Greek ἀράχνη (arákhnē, “spider”).",
  "head_templates": [
    {
      "args": {
        "1": "fr",
        "2": "prefix"
      },
      "expansion": "arachno-",
      "name": "head"
    }
  ],
  "lang": "French",
  "lang_code": "fr",
  "pos": "prefix",
  "senses": [
    {
      "categories": [
        "French 3-syllable words",
        "French entries with incorrect language header",
        "French lemmas",
        "French prefixes",
        "French terms derived from Ancient Greek",
        "French terms with IPA pronunciation",
        "Pages using catfix",
        "Pages with 3 entries",
        "Pages with entries"
      ],
      "glosses": [
        "arachno-"
      ],
      "links": [
        [
          "arachno-",
          "arachno-#English"
        ]
      ],
      "synonyms": [
        {
          "word": "aranéo-"
        }
      ],
      "tags": [
        "morpheme"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "/a.ʁak.no/"
    }
  ],
  "word": "arachno-"
}