Where does “fastness” come from?

Fastness derives from Middle English fastnesse, from Old English fæstnes (Old English -nes suffix), from Proto-Germanic fastuz with the Proto-Germanic -inassuz suffix, ultimately from Proto-Germanic -inōną.

fastness (English): A secure or fortified place; a stronghold, a...

Definitions

  1. A secure or fortified place; a stronghold, a...

Ancestry of “fastness”, step by step

fastness traces back through two separate lines of ancestry.

via Middle English fastnesse

StepLanguageWordMeaning
1Middle Englishfastnesse
2Old Englishfæstnesfastness, firmness, firmament, fortification,...
3Old English-nesUsed to form abstract nouns, usually from...
4Proto-West Germanic-nassīUsed to form abstract nouns, usually from...
5Proto-Germanic-inassuz-ness
6Proto-West Germanic-ness, -th
7Proto-Germanic-į̄-th
8Proto-Indo-European-íh₂
9Proto-Indo-European-h₂Creates collective nouns, which refer to groups...

via Middle English festnesse

StepLanguageWordMeaning
1Middle Englishfestnessefirmness; certainty; stronghold; firmament
Every word from Proto-Indo-European -h₂