Where does “generative” come from?

Generative comes from Middle English generatyve, meaning capable of producing or generating.

generative (English): Having the power of generating, propagating,...

Definitions

Step	Language	Word	Meaning
1	Middle English	generatyve	—
2	Latin	generō	—
3	Latin	genus	birth, origin, lineage, descent; kind, type,...
4	Proto-Italic	genos	lineage, origin
5	Proto-Indo-European	ǵénh₁os	race, lineage
6	Proto-Indo-European	ǵenh₁-	to produce, to beget, to give birth

generative — Etymology, Origin & Word History | Etymology Explorer