"-z" meaning in Old French

{
  "head_templates": [
    {
      "args": {
        "1": "fro",
        "2": "suffix"
      },
      "expansion": "-z",
      "name": "head"
    }
  ],
  "lang": "Old French",
  "lang_code": "fro",
  "pos": "suffix",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Old French entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Old French links with redundant target parameters",
          "parents": [
            "Links with redundant target parameters",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with raw sortkeys",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "text": "mort (“dead”) (oblique singular) → morz (“dead”) (oblique plural)"
        },
        {
          "english": "(please add an English translation of this quotation)",
          "ref": "c. 1100s, Marie de France, Equitan",
          "text": "Femme espuse ot li seneschals,\nDunt puis vient el païs granz mal[s]",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Replaces -ts at the end of a word."
      ],
      "id": "en--z-fro-suffix-q2i19xCv",
      "tags": [
        "morpheme"
      ]
    }
  ],
  "word": "-z"
}

{
  "head_templates": [
    {
      "args": {
        "1": "fro",
        "2": "suffix"
      },
      "expansion": "-z",
      "name": "head"
    }
  ],
  "lang": "Old French",
  "lang_code": "fro",
  "pos": "suffix",
  "senses": [
    {
      "categories": [
        "Old French entries with incorrect language header",
        "Old French lemmas",
        "Old French links with redundant target parameters",
        "Old French suffixes",
        "Old French terms with quotations",
        "Pages with raw sortkeys",
        "Quotation templates to be cleaned",
        "Requests for translations of Old French quotations"
      ],
      "examples": [
        {
          "text": "mort (“dead”) (oblique singular) → morz (“dead”) (oblique plural)"
        },
        {
          "english": "(please add an English translation of this quotation)",
          "ref": "c. 1100s, Marie de France, Equitan",
          "text": "Femme espuse ot li seneschals,\nDunt puis vient el païs granz mal[s]",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Replaces -ts at the end of a word."
      ],
      "tags": [
        "morpheme"
      ]
    }
  ],
  "word": "-z"
}