"ooff" meaning in English

{
  "lang": "English",
  "lang_code": "en",
  "pos": "intj",
  "senses": [
    {
      "alt_of": [
        {
          "word": "oof"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "2013, Thomas W. Dawson, The Mystery of the Old Gold Mine, page 208:",
          "text": "Quickly he turned back, his shoes digging in, churning up the sand as he scurried along the beach. The next thing he knew—ooff—he was flat on the ground, his head slamming against the sandy surface.",
          "type": "quote"
        }
      ],
      "glosses": [
        "Alternative form of oof"
      ],
      "id": "en-ooff-en-intj-CyE9YAPb",
      "links": [
        [
          "oof",
          "oof#English"
        ]
      ],
      "tags": [
        "alt-of",
        "alternative"
      ]
    }
  ],
  "word": "ooff"
}

{
  "lang": "English",
  "lang_code": "en",
  "pos": "intj",
  "senses": [
    {
      "alt_of": [
        {
          "word": "oof"
        }
      ],
      "categories": [
        "English entries with incorrect language header",
        "English interjections",
        "English lemmas",
        "English terms with quotations",
        "Pages with 1 entry",
        "Pages with entries",
        "Quotation templates to be cleaned"
      ],
      "examples": [
        {
          "ref": "2013, Thomas W. Dawson, The Mystery of the Old Gold Mine, page 208:",
          "text": "Quickly he turned back, his shoes digging in, churning up the sand as he scurried along the beach. The next thing he knew—ooff—he was flat on the ground, his head slamming against the sandy surface.",
          "type": "quote"
        }
      ],
      "glosses": [
        "Alternative form of oof"
      ],
      "links": [
        [
          "oof",
          "oof#English"
        ]
      ],
      "tags": [
        "alt-of",
        "alternative"
      ]
    }
  ],
  "word": "ooff"
}