Where does “stérile” come from?

stérile (Middle French) comes from Latin sterilis, from Proto-Indo-European ster- — sterile, infertile.

Ancestry of “stérile”, step by step

Step	Language	Word	Meaning
1	Latin	sterilis	barren, sterile; unprofitable, futile
2	Proto-Indo-European	ster-	sterile, infertile

stérile — Etymology, Origin & Word History | Etymology Explorer