"-o" meaning in Esperanto

{
  "etymology_text": "* From the masculine singular of the Romance languages, such as Italian (amico); perhaps also the neuter singular common to all Slavic languages (окно (okno))\n* Perhaps from the above (Italian quello, Russian то (to))\n* Possibly derived from Greek second declension syllabic nucleus -o, from which plural -oj in greek is likely also derived.",
  "head_templates": [
    {
      "args": {
        "1": "eo",
        "2": "suffix"
      },
      "expansion": "-o",
      "name": "head"
    }
  ],
  "lang": "Esperanto",
  "lang_code": "eo",
  "pos": "suffix",
  "senses": [
    {
      "categories": [
        {
          "_dis": "100 0",
          "kind": "other",
          "name": "Esperanto BRO1",
          "parents": [],
          "source": "w+disamb"
        },
        {
          "_dis": "96 4",
          "kind": "other",
          "name": "Esperanto entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w+disamb"
        }
      ],
      "examples": [
        {
          "text": "amiko (“friend”)"
        },
        {
          "text": "patro (“father”)"
        },
        {
          "text": "vorto (“word”)"
        }
      ],
      "glosses": [
        "Nominal suffix. Most Esperanto nouns end in -o. (A few nouns end in -aŭ, and with some writers some feminine names end in -a.)"
      ],
      "head_nr": 1,
      "id": "en--o-eo-suffix-NO1IhXmT",
      "links": [
        [
          "Nominal",
          "nominal"
        ],
        [
          "noun",
          "noun"
        ],
        [
          "-aŭ",
          "-aŭ#Esperanto"
        ],
        [
          "-a",
          "-a#Esperanto"
        ]
      ],
      "tags": [
        "morpheme"
      ]
    },
    {
      "categories": [
        {
          "kind": "other",
          "name": "Esperanto correlatives",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "text": "kio (“what?, what”)"
        },
        {
          "text": "tio (“that”)"
        },
        {
          "text": "ĉio (“everything”)"
        },
        {
          "text": "io (“something”)"
        },
        {
          "text": "nenio (“nothing”)"
        }
      ],
      "glosses": [
        "-thing. (correlative object ending.)"
      ],
      "head_nr": 1,
      "id": "en--o-eo-suffix-P1jgu8LV",
      "tags": [
        "morpheme"
      ]
    }
  ],
  "sounds": [
    {
      "audio": "LL-Q143 (epo)-Lepticed7--o.wav",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/8/87/LL-Q143_%28epo%29-Lepticed7--o.wav/LL-Q143_%28epo%29-Lepticed7--o.wav.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/8/87/LL-Q143_%28epo%29-Lepticed7--o.wav/LL-Q143_%28epo%29-Lepticed7--o.wav.ogg"
    },
    {
      "ipa": "/o/"
    }
  ],
  "word": "-o"
}

{
  "categories": [
    "Esperanto BRO1",
    "Esperanto entries with incorrect language header",
    "Esperanto lemmas",
    "Esperanto suffixes",
    "Pages with 32 entries",
    "Pages with entries"
  ],
  "etymology_text": "* From the masculine singular of the Romance languages, such as Italian (amico); perhaps also the neuter singular common to all Slavic languages (окно (okno))\n* Perhaps from the above (Italian quello, Russian то (to))\n* Possibly derived from Greek second declension syllabic nucleus -o, from which plural -oj in greek is likely also derived.",
  "head_templates": [
    {
      "args": {
        "1": "eo",
        "2": "suffix"
      },
      "expansion": "-o",
      "name": "head"
    }
  ],
  "lang": "Esperanto",
  "lang_code": "eo",
  "pos": "suffix",
  "senses": [
    {
      "examples": [
        {
          "text": "amiko (“friend”)"
        },
        {
          "text": "patro (“father”)"
        },
        {
          "text": "vorto (“word”)"
        }
      ],
      "glosses": [
        "Nominal suffix. Most Esperanto nouns end in -o. (A few nouns end in -aŭ, and with some writers some feminine names end in -a.)"
      ],
      "head_nr": 1,
      "links": [
        [
          "Nominal",
          "nominal"
        ],
        [
          "noun",
          "noun"
        ],
        [
          "-aŭ",
          "-aŭ#Esperanto"
        ],
        [
          "-a",
          "-a#Esperanto"
        ]
      ],
      "tags": [
        "morpheme"
      ]
    },
    {
      "categories": [
        "Esperanto correlatives"
      ],
      "examples": [
        {
          "text": "kio (“what?, what”)"
        },
        {
          "text": "tio (“that”)"
        },
        {
          "text": "ĉio (“everything”)"
        },
        {
          "text": "io (“something”)"
        },
        {
          "text": "nenio (“nothing”)"
        }
      ],
      "glosses": [
        "-thing. (correlative object ending.)"
      ],
      "head_nr": 1,
      "tags": [
        "morpheme"
      ]
    }
  ],
  "sounds": [
    {
      "audio": "LL-Q143 (epo)-Lepticed7--o.wav",
      "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/8/87/LL-Q143_%28epo%29-Lepticed7--o.wav/LL-Q143_%28epo%29-Lepticed7--o.wav.mp3",
      "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/8/87/LL-Q143_%28epo%29-Lepticed7--o.wav/LL-Q143_%28epo%29-Lepticed7--o.wav.ogg"
    },
    {
      "ipa": "/o/"
    }
  ],
  "word": "-o"
}

{
  "called_from": "page/1713/20221215",
  "msg": "later head without list of senses,template node #, -o/Esperanto",
  "path": [
    "-o"
  ],
  "section": "Esperanto",
  "subsection": "suffix",
  "title": "-o",
  "trace": ""
}