nor
A word used to connect two negative ideas together.
Nor is a connecting word that links two negative ideas together. When you say “I don't like broccoli, nor do I like Brussels sprouts,” you're using nor to add a second thing you dislike to the first.
The word nor works with “neither” like bread works with butter. You might say “neither my sister nor my brother wants to do the dishes” when both of them are refusing. Notice how nor keeps the negative feeling going: you're not switching to something positive, you're piling on another negative thing.
You'll often see nor in formal writing or when someone wants to sound emphatic. Instead of saying “I didn't study and I didn't do my homework,” you could say “I neither studied nor did my homework” (though you'd probably regret both choices when test day arrived).
Think of nor as the word that says “and this negative thing too.” It's pickier about its placement than words like “and” or “but,” which is why it sometimes trips people up. But once you get the hang of it, nor gives you a clean, powerful way to connect related negative statements.