Etymology tree Proto-Indo-European *de Proto-Indo-European *-h₁ Proto-Indo-European *déh₁ Proto-Italic *dē Latin dē Latin dē-der. English de- English fibrillate English defibrillate Proto-Indo-European *-tōr Proto-Italic *-tōr Latin -tor Latin -ātor Old French -eorbor. Middle English -our ▲ Latin -torlbor. English -or English defibrillatorbor. Polish defibrylator Borrowed from English…