Middle English word appreven comes from Latin probo, Latin ad ((direction) toward, to, on, up to, for.)

Detailed word origin of appreven

Dictionary entry	Language	Definition
probo	Latin (lat)	I acquit, exonerate. I approve, commend. I demonstrate, prove. I test, inspect.
ad	Latin (lat)	(direction) toward, to, on, up to, for.
approbare	Latin (lat)
approuvir	Old French (fro)
aproven	Middle English (enm)	To prove.

Words with the same origin as appreven