Where does “unfastness” come from?

unfastness (English) comes from English unfast, from English fast, from Middle English fast, from Old English fæste, from Old English -e, from Old English -en, from Old Norse -inn, from Proto-Norse -īna- — adjectival suffix.

unfastness (English): Lack of closeness, as of fibre; porousness

Definitions

  1. Lack of closeness, as of fibre; porousness

Ancestry of “unfastness”, step by step

unfastness traces back through two separate lines of ancestry.

via English unfast

StepLanguageWordMeaning
1EnglishunfastTo loose; release; Not fast or safe; not secure
2EnglishfastFirmly or securely fixed in place; stable; Firm...
3Middle Englishfastfast quickly
4Old Englishfæstefirmly, fastly, tightly
5Old English-eforming adverbs from adjectives; -ly
6Old English-enmæġþ + API → mæġden; cocc + API → cycen, cicen;...
7Old Norse-innUsed to create adjectives from nouns, meaning...
8Proto-Norse-īna-
9Proto-Germanic-īnaz-en
10Proto-Indo-European-iHnosCreates adjectives of materials
11Proto-Indo-European-no-adjectival suffix

via English Ness

StepLanguageWordMeaning
1EnglishNessAn Ulster princess and the mother of Conchobar mac Nessa and Findchoem in the Ulster Cycle of Irish mythology. Daughter of Eochaid Sálbuide. Also the mother of Cormac Cond Longas by incest with Conchobar mac Nessa
2Middle Englishnesse
3Old Englishnæsnot, not at all; not; first/third-person singular...
4Proto-Germanicnasjąfoothill; headland; cape
5Proto-Indo-Europeannéh₂snose
Every word from Proto-Indo-European -no-
unfastness — Etymology, Origin & Word History | Etymology Explorer