Hitler would have been greatly offended if you called him a Nazi. Though embraced by extreme alt-righters today, the fascists of WWII Germany generally avoided the term, which was a colloquialism for "dunce" in southern Germany before the war. The word got applied to them when fleeing anti-fascist Germans cleverly abbreviated Nationalsozialist, an already shortened version of the party name. This spread to the countries they migrated to as a general term to encompass Hitler's group (who would've preferred NSDAP). The pejorative colloquialism Nazi was a nickname for Ignatz, a common name much like "John", with a country-bumpkin connotation of stupidity and ignorance. This in turn likely derives from Latin Ignatius, a Biblical name with possible origins in Ancient Greek, or Latin, or something. Honestly, etymologists aren't completely sure. But we are positive about the whole Nazi-insult thing. Believe me.
Hello! I'm Adam Aleksic, a sophomore studying government and linguistics at Harvard University, where I co-founded the Harvard Undergraduate Linguistics Society. In addition to etymology, I also really enjoy politics, vexillology, geography, board games, conlanging, and law.