Braguettes were important back then, especially as part of a suit of armour. Henry VIII (who was rather concerned about his reproductive abilities) had armour like this:
"I'm sorry, Pocahontas, but I've got to go back to England and write a nautical dictionary."
So now you've got an architectural thing called a bracket. But if you want to be really secure, you should use a double bracket. A double bracket looks like this:
So what are you going to call this ] bit of punctuation?
That, my child, is correct. You're going to call it a bracket, because it looks like something that looks like a codpiece. My etymological dictionary says that this happened in 1750, but I just found a usage from 1711 in William Whiston's racy classic Primitive Christianity Revived.
This earlier citation makes me a clever, clever, clever little boy.
Now look at your computer keyboard.
Y U I O P [ ].
And so bracket can be traced back to Asterix.
[ ] -> *
Codpieces have nothing to do with cod