From Wiktionary, the free dictionary
From Proto-West Germanic *-siunī. Cognate with Old High German -siuni. Equivalent to sīen + -e, literally “with a certain sight.”
-sīene
- relating to sight: -seen, -visible, -sighted
- ēage (“eye”) + -siene → ēagsīene (“apparent”)
- sċearp (“sharp”) + -siene → sċearpsīene (“sharpsighted”)
- seld- (“rare”) + -siene → seldsīene (“strange”)
- þurh (“through”) + -siene → þurhsīene (“seethrough”)