testify

The story

1. Latin · derived fromtestificārī“to bear witness”
2. Old French · derived fromtestifier
3. Middle English · inherited fromtestifien
4. English todaytestify

PIE word *tréyes From Middle English testifien, borrowed from Old French testifier, from Latin testificārī (“to bear witness”), from testis (“a witness”) + facere (“to make”). See -fy.