Where does “ergativeness” come from?

ergativeness (English) comes from English ergative, from Ancient Greek ἐργάτης, from Ancient Greek ἔργον, from Proto-Hellenic wérgon, from Proto-Indo-European wérǵom, from Proto-Indo-European werǵ- — to make.

Ancestry of “ergativeness”, step by step

ergativeness traces back through two separate lines of ancestry.

via English ergative

StepLanguageWordMeaning
1EnglishergativeUsed of various situations where the subjects of...
2Ancient Greekἐργάτηςworker, workman, labourer; capstan, windlass,...
3Ancient Greekἔργονdeed, doing, action; labour, work, task;...
4Proto-Hellenicwérgonwork
5Proto-Indo-Europeanwérǵomwork
6Proto-Indo-Europeanwerǵ-to make

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 werǵ-Every word from Proto-Indo-European wérǵomEvery word from Proto-Hellenic wérgon