Where does “futile” come from?

futile (Middle French) comes from Latin futilis, from Proto-Indo-European ǵʰew- — to pour.

Ancestry of “futile”, step by step

Step	Language	Word	Meaning
1	Latin	futilis	that easily pours out; that can not contain,...
2	Proto-Indo-European	ǵʰew-	to pour

futile — Etymology, Origin & Word History | Etymology Explorer