"por-" meaning in Old French

{
  "etymology_templates": [
    {
      "args": {
        "1": "fro",
        "2": "la",
        "3": "prō"
      },
      "expansion": "Latin prō",
      "name": "uder"
    }
  ],
  "etymology_text": "From Latin prō.",
  "head_templates": [
    {
      "args": {
        "1": "fro",
        "2": "prefix"
      },
      "expansion": "por-",
      "name": "head"
    }
  ],
  "lang": "Old French",
  "lang_code": "fro",
  "pos": "prefix",
  "senses": [
    {
      "categories": [],
      "examples": [
        {
          "english": "to go through",
          "text": "poraler",
          "type": "example"
        }
      ],
      "glosses": [
        "through"
      ],
      "id": "en-por--fro-prefix-nGcl3Caa",
      "links": [
        [
          "through",
          "through"
        ]
      ],
      "tags": [
        "morpheme"
      ]
    },
    {
      "categories": [],
      "examples": [
        {
          "english": "to follow; to pursue",
          "text": "porchacier",
          "type": "example"
        }
      ],
      "glosses": [
        "used as a general intensifier"
      ],
      "id": "en-por--fro-prefix-tCgAlOKe",
      "tags": [
        "morpheme"
      ]
    }
  ],
  "synonyms": [
    {
      "_dis1": "0 0",
      "word": "pour-"
    },
    {
      "_dis1": "0 0",
      "word": "pro-"
    },
    {
      "_dis1": "0 0",
      "word": "pur-"
    }
  ],
  "word": "por-"
}

{
  "categories": [
    "Old French entries with incorrect language header",
    "Old French lemmas",
    "Old French prefixes",
    "Old French terms derived from Latin",
    "Old French undefined derivations",
    "Pages with 2 entries",
    "Pages with entries"
  ],
  "etymology_templates": [
    {
      "args": {
        "1": "fro",
        "2": "la",
        "3": "prō"
      },
      "expansion": "Latin prō",
      "name": "uder"
    }
  ],
  "etymology_text": "From Latin prō.",
  "head_templates": [
    {
      "args": {
        "1": "fro",
        "2": "prefix"
      },
      "expansion": "por-",
      "name": "head"
    }
  ],
  "lang": "Old French",
  "lang_code": "fro",
  "pos": "prefix",
  "senses": [
    {
      "categories": [
        "Old French terms with usage examples"
      ],
      "examples": [
        {
          "english": "to go through",
          "text": "poraler",
          "type": "example"
        }
      ],
      "glosses": [
        "through"
      ],
      "links": [
        [
          "through",
          "through"
        ]
      ],
      "tags": [
        "morpheme"
      ]
    },
    {
      "categories": [
        "Old French terms with usage examples"
      ],
      "examples": [
        {
          "english": "to follow; to pursue",
          "text": "porchacier",
          "type": "example"
        }
      ],
      "glosses": [
        "used as a general intensifier"
      ],
      "tags": [
        "morpheme"
      ]
    }
  ],
  "synonyms": [
    {
      "word": "pour-"
    },
    {
      "word": "pro-"
    },
    {
      "word": "pur-"
    }
  ],
  "word": "por-"
}