"rusum" meaning in Latin

{
  "forms": [
    {
      "form": "rūsum",
      "tags": [
        "canonical"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "la",
        "2": "adverb",
        "head": "rūsum"
      },
      "expansion": "rūsum",
      "name": "head"
    }
  ],
  "lang": "Latin",
  "lang_code": "la",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "rūrsum"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "Latin entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "english": "And in this way, some [say] \"dossum\" with two s's instead of \"dorsum\" with an r to sound gentler. But to all, r is a sunk letter in \"rusum\" and \"retrosum\".]",
          "ref": "[98–138 CE, Velius Longus, edited by T.H.G. Keil, Liber de orthographia (Grammatici Latini; VII), published 1880, page 79, lines 4–6",
          "text": "sic et dossum per duo s quam per r dorsum quidam ut lenius enuntiaverunt. ac tota r littera sublata est in eo quod est rusum et retrosum.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Alternative form of rūrsum"
      ],
      "id": "en-rusum-la-noun--OwL8eRQ",
      "links": [
        [
          "rūrsum",
          "rursum#Latin"
        ]
      ],
      "tags": [
        "alt-of",
        "alternative"
      ]
    }
  ],
  "word": "rusum"
}

{
  "forms": [
    {
      "form": "rūsum",
      "tags": [
        "canonical"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "1": "la",
        "2": "adverb",
        "head": "rūsum"
      },
      "expansion": "rūsum",
      "name": "head"
    }
  ],
  "lang": "Latin",
  "lang_code": "la",
  "pos": "noun",
  "senses": [
    {
      "alt_of": [
        {
          "word": "rūrsum"
        }
      ],
      "categories": [
        "Latin adverbs",
        "Latin entries with incorrect language header",
        "Latin lemmas",
        "Latin terms with quotations"
      ],
      "examples": [
        {
          "english": "And in this way, some [say] \"dossum\" with two s's instead of \"dorsum\" with an r to sound gentler. But to all, r is a sunk letter in \"rusum\" and \"retrosum\".]",
          "ref": "[98–138 CE, Velius Longus, edited by T.H.G. Keil, Liber de orthographia (Grammatici Latini; VII), published 1880, page 79, lines 4–6",
          "text": "sic et dossum per duo s quam per r dorsum quidam ut lenius enuntiaverunt. ac tota r littera sublata est in eo quod est rusum et retrosum.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Alternative form of rūrsum"
      ],
      "links": [
        [
          "rūrsum",
          "rursum#Latin"
        ]
      ],
      "tags": [
        "alt-of",
        "alternative"
      ]
    }
  ],
  "word": "rusum"
}