Where does “felować” come from?

felować (Polish) comes from German fehlen, from Middle High German vælen, from Old French faillir, from Latin fallēre.

Ancestry of “felować”, step by step

Step	Language	Word	Meaning
1	German	fehlen	to lack; to be absent from, to be missing from,...
2	Middle High German	vælen	—
3	Old French	faillir	alternative infinitive of falir; to fail, err
4	Latin	fallēre	—