The story
- Proto-West Germanic · inherited from*blīþinassī
- Old English · inherited fromblīþnes
- Middle English · inherited from*blithenesse
- English todayblitheness
From Middle English *blithenesse, from Old English blīþnes, from Proto-West Germanic *blīþinassī, equivalent to blithe + -ness. Cognate with West Frisian blidens (“blitheness, joy”), Old High German blīdnissa (“joy”).
Etymology from Wiktionary, CC BY-SA 4.0.