Where does “keenness” come from?

Keenness derives from English keen, from Irish caoin, from Old Irish caín, ultimately from Proto-Indo-European ǵneh₃-, with formative elements from Proto-Germanic -inōną.

keenness (English): sharpness or cutting ability; astuteness or...

Definitions

  1. sharpness or cutting ability; astuteness or...

Ancestry of “keenness”, step by step

keenness traces back through two separate lines of ancestry.

via English keen

StepLanguageWordMeaning
1EnglishkeenOften with a prepositional phrase, or with to and...
2Irishcaoinsmooth, delicate, polished; kind, gentle,...
3Middle Irishcaínsmooth finished side; "especially" the outer...
4Old Irishcaínfine, good; fair, beautiful
5Proto-Celtic*kanisnice, good

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

Words derived from “keenness

Every word from Proto-Celtic *kanisEvery word from Old Irish caínEvery word from Middle Irish caín