Among hardcore hobbyists like Civil War reenactors, a person who is so obsessed with historical accuracy that they demand ridiculous levels of perfectionism from others
"We were already in the field when that Stitch Nazi told us the thread count of our uniforms would never pass muster."
An adult who never got out of his edgy kid phase, thinks that tasteless antisemitic jokes are still funny, and still tries to piss people off just so they can call them a pussy for being offended by it.
Some baby nazi just drew swastikas all over the stalls in the mall bathroom.
'slang-grammar nazi' - A person who always corrects people on their usage of slang, colloquial, memes, etc.
*person looks at a box of donuts* - "dat donuts!"
slammer nazi - "no man, it's Dem Donuts"
"I like 50-cent"
slammer nazi - "no man, it's fiddy cent"
Someone who is obsessed with the continuity of a particular universe such as Star Trek or Star Wars.
That continuity nazi kept going on and on about how the events of Star Trek Generations don't line up with the TNG episode Relics.
A climate change freak who controls everyone like the Nazi's to try and stop climate change.
That Greta Thunberg is a Climate Nazi! She is trying to control everyone!
A person who likes to control the drinking (or lack of) at any particular event or gathering.
Andrea was being a real drink nazi at the birthday party, trying to make everybody drink with her...
Someone who repeatedly tells everyone they will bring delicious cupcakes but then never do.
Annaliese told me she would bring some cupcakes but then she didn’t, she is such a Cupcake Nazi.