skin
You said Later and wider borrowings. It's Old Norse.
How that family writes these sounds
| /sk/ at the start | sk-, never sc- or sh-sky, skin, skirt, skull |
What gives it away on the page
| sk- | Native sc- had already softened to sh-, so a hard sk- came from somewhere else.sky, skin, skirt, skill, skull |
Placing it without the spelling
| a hard /sk/ at the start | Old Norsesky, skin, skirt, skull |
Another word → · the full story of skin · Old Norse in the guide