"serpentajn" meaning in Esperanto

{
  "head_templates": [
    {
      "args": {},
      "expansion": "serpentajn",
      "name": "eo-head"
    }
  ],
  "hyphenation": [
    "ser‧pent‧ajn"
  ],
  "lang": "Esperanto",
  "lang_code": "eo",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Esperanto entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "form_of": [
        {
          "word": "serpenta"
        }
      ],
      "glosses": [
        "accusative plural of serpenta"
      ],
      "id": "en-serpentajn-eo-noun-GttNqA4V",
      "links": [
        [
          "serpenta",
          "serpenta#Esperanto"
        ]
      ],
      "tags": [
        "accusative",
        "form-of",
        "plural"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "[serˈpentajn]"
    },
    {
      "rhymes": "-entajn"
    }
  ],
  "word": "serpentajn"
}

{
  "head_templates": [
    {
      "args": {},
      "expansion": "serpentajn",
      "name": "eo-head"
    }
  ],
  "hyphenation": [
    "ser‧pent‧ajn"
  ],
  "lang": "Esperanto",
  "lang_code": "eo",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "Esperanto adjective forms",
        "Esperanto entries with incorrect language header",
        "Esperanto non-lemma forms",
        "Esperanto terms with IPA pronunciation",
        "Rhymes:Esperanto/entajn"
      ],
      "form_of": [
        {
          "word": "serpenta"
        }
      ],
      "glosses": [
        "accusative plural of serpenta"
      ],
      "links": [
        [
          "serpenta",
          "serpenta#Esperanto"
        ]
      ],
      "tags": [
        "accusative",
        "form-of",
        "plural"
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "[serˈpentajn]"
    },
    {
      "rhymes": "-entajn"
    }
  ],
  "word": "serpentajn"
}