Latin word probare comes from Proto-Indo-European *pr̥-, Proto-Indo-European *bhu-

Detailed word origin of probare

Dictionary entry	Language	Definition
*pr̥-	Proto-Indo-European (ine-pro)
*bhu-	Proto-Indo-European (ine-pro)
*pro-bhwo-	Proto-Indo-European (ine-pro)
probus	Latin (lat)	(morally) upright, honest, virtuous. Good, serviceable, excellent, superior, able.
probo	Latin (lat)	I acquit, exonerate. I approve, commend. I demonstrate, prove. I test, inspect.