I found this regarding the origin of Vendetta: “a prolonged and bitter feud” is a borrowing from Italian, derived from Latin vindicta “vengeance,” from vindex “defender,” which is also the source of avenger, revenge, vengeance, and vindicate.

Honestly, I've never heard of the first definition of vendetta. I've only ever seen and heard it used in the second definition's context. How interesting.

(Also, I just have to ask... What the hell is that Twitter GIF supposed to represent? haha)