"-sk" meaning in Swedish

{
  "etymology_templates": [
    {
      "args": {
        "1": "sv",
        "2": "non",
        "3": "-skr"
      },
      "expansion": "Old Norse -skr",
      "name": "der"
    },
    {
      "args": {
        "1": "sv",
        "2": "gem-pro",
        "3": "*-iskaz"
      },
      "expansion": "Proto-Germanic *-iskaz",
      "name": "der"
    }
  ],
  "etymology_text": "From Old Norse -skr, from Proto-Germanic *-iskaz.",
  "head_templates": [
    {
      "args": {
        "1": "sv",
        "2": "suffix"
      },
      "expansion": "-sk",
      "name": "head"
    }
  ],
  "lang": "Swedish",
  "lang_code": "sv",
  "pos": "suffix",
  "senses": [
    {
      "alt_of": [
        {
          "word": "-isk"
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "Swedish entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Alternative form of -isk"
      ],
      "id": "en--sk-sv-suffix-vX0uAKYY",
      "links": [
        [
          "-isk",
          "-isk#Swedish"
        ]
      ],
      "tags": [
        "alt-of",
        "alternative",
        "morpheme"
      ]
    }
  ],
  "word": "-sk"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "sv",
        "2": "non",
        "3": "-skr"
      },
      "expansion": "Old Norse -skr",
      "name": "der"
    },
    {
      "args": {
        "1": "sv",
        "2": "gem-pro",
        "3": "*-iskaz"
      },
      "expansion": "Proto-Germanic *-iskaz",
      "name": "der"
    }
  ],
  "etymology_text": "From Old Norse -skr, from Proto-Germanic *-iskaz.",
  "head_templates": [
    {
      "args": {
        "1": "sv",
        "2": "suffix"
      },
      "expansion": "-sk",
      "name": "head"
    }
  ],
  "lang": "Swedish",
  "lang_code": "sv",
  "pos": "suffix",
  "senses": [
    {
      "alt_of": [
        {
          "word": "-isk"
        }
      ],
      "categories": [
        "Swedish entries with incorrect language header",
        "Swedish lemmas",
        "Swedish suffixes",
        "Swedish terms derived from Old Norse",
        "Swedish terms derived from Proto-Germanic"
      ],
      "glosses": [
        "Alternative form of -isk"
      ],
      "links": [
        [
          "-isk",
          "-isk#Swedish"
        ]
      ],
      "tags": [
        "alt-of",
        "alternative",
        "morpheme"
      ]
    }
  ],
  "word": "-sk"
}