Where does “unflexibleness” come from?

unflexibleness (English) comes from English unflexible, from English flexible, from Middle French flexible, from Latin flexibilis, from Latin -bilis, from Proto-Italic -ðlis, from Proto-Indo-European -dʰlis, from Proto-Indo-European -dʰlom — Alternative form of *-trom; instrumental suffix;...

Ancestry of “unflexibleness”, step by step

unflexibleness traces back through two separate lines of ancestry.

via English unflexible

StepLanguageWordMeaning
1EnglishunflexibleNot flexible
2EnglishflexibleCapable of being flexed or bent without breaking;...
3Middle Frenchflexible
4Latinflexibilisflexible, pliant, able to be bent; tractable,...
5Latin-bilis-ble
6Proto-Italic-ðlisForms adjectives from verb stems indicating capacity or worth of being acted on
7Proto-Indo-European-dʰlis
8Proto-Indo-European-dʰlomAlternative form of *-trom; instrumental 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 -dʰlomEvery word from Latin -bilisEvery word from Latin flexibilis