"fjirtjin" meaning in West Frisian

{
  "etymology_templates": [
    {
      "args": {
        "1": "fy",
        "2": "ofs",
        "3": "fiūwertīne"
      },
      "expansion": "Old Frisian fiūwertīne",
      "name": "inh"
    },
    {
      "args": {
        "1": "fy",
        "2": "gem-pro",
        "3": "*fedurtehun"
      },
      "expansion": "Proto-Germanic *fedurtehun",
      "name": "inh"
    }
  ],
  "etymology_text": "From Old Frisian fiūwertīne, from Proto-Germanic *fedurtehun.",
  "head_templates": [
    {
      "args": {
        "1": "fy",
        "2": "numeral"
      },
      "expansion": "fjirtjin",
      "name": "head"
    }
  ],
  "lang": "West Frisian",
  "lang_code": "fy",
  "pos": "num",
  "senses": [
    {
      "categories": [
        {
          "kind": "topical",
          "name": "West Frisian cardinal numbers",
          "parents": [
            "Cardinal numbers",
            "Numbers",
            "All topics",
            "Terms by semantic function",
            "Fundamental"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "West Frisian entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "fourteen"
      ],
      "id": "en-fjirtjin-fy-num-~vj0HNzS",
      "links": [
        [
          "fourteen",
          "fourteen"
        ]
      ]
    }
  ],
  "word": "fjirtjin"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "fy",
        "2": "ofs",
        "3": "fiūwertīne"
      },
      "expansion": "Old Frisian fiūwertīne",
      "name": "inh"
    },
    {
      "args": {
        "1": "fy",
        "2": "gem-pro",
        "3": "*fedurtehun"
      },
      "expansion": "Proto-Germanic *fedurtehun",
      "name": "inh"
    }
  ],
  "etymology_text": "From Old Frisian fiūwertīne, from Proto-Germanic *fedurtehun.",
  "head_templates": [
    {
      "args": {
        "1": "fy",
        "2": "numeral"
      },
      "expansion": "fjirtjin",
      "name": "head"
    }
  ],
  "lang": "West Frisian",
  "lang_code": "fy",
  "pos": "num",
  "senses": [
    {
      "categories": [
        "West Frisian cardinal numbers",
        "West Frisian entries with incorrect language header",
        "West Frisian lemmas",
        "West Frisian numerals",
        "West Frisian terms derived from Old Frisian",
        "West Frisian terms derived from Proto-Germanic",
        "West Frisian terms inherited from Old Frisian",
        "West Frisian terms inherited from Proto-Germanic"
      ],
      "glosses": [
        "fourteen"
      ],
      "links": [
        [
          "fourteen",
          "fourteen"
        ]
      ]
    }
  ],
  "word": "fjirtjin"
}