Here in the UK I have heard all of these different definitions for the word ‘nonce’, except the ‘cryptographic nonce’ meaning, which sounds really interesting.
Yes; I do seem to remember this in the UK too. The word seems to have changed from a fairly innocuous term for an idiot to a term describing sex offenders, perhaps during the 1970s.
American as well. I am completely unfamiliar with “nonce” meaning “now.” For me it’s only in the phrase “nonce word” or in the UK sexual predator meaning, as I consume a lot of UK media.
Huh, I was only aware of the “now” and “nonce word” meanings, wasn’t aware of the other meaning until this thread.
It’s pretty well established the pedophile meaning is UK / Commonwealth slang not used at all in the USA.
Like most things with cryptography it sounds interesting, but boils down to a simple concept. The most common usage is to prevent Replay Attacks.
If Alice is sending encrypted messages to Bob, and Eve copies one of them and then sends it to Bob pretending to be Alice, how does Bob distinguish between the two? They are identical so if one is valid the other must be as well right?
Well, one thing Alice and Bob can do is make a rule - every message has to have a unique number included in the encrypted portion. We call that number a nonce. Because it has to be unique it can’t be used a second time. Both Bob and Alice, when decrypting messages from each other, check to make sure the number hasn’t ever been used before in their communications. So when Eve’s message arrives, Bob sees the duplicate number and knows it’s not legitimate.
Eve can’t change the number either because it’s encrypted and she doesn’t have the key (if she did, then Alice and Bob are already compromised). Thus the potential attack is thwarted.
I’ve heard both ‘ponce’ and ‘nancy boy’ as derogatory terms. Maybe if you mush them together, they turn into ‘nonce’.
That was my understanding. I was pretty shocked to hear it was a slang term, and for wahat.
“Ponce” and “nancy boy” are just insults meaning effeminate (and implied gay), similar to calling a boy or man a “sissy”. I doubt this is the etymology of “nonce”, but I suppose I can see how one might connect them as derogatory terms.
Ponce is also complex and interesting. Historically it meant a pimp, someone live on the immoral earnings of a prostitute, and didn’t imply effeminacy. Later it implied a flashy, pretentious man, probably because they were successful as a pimp. Pretentiousness was also sometimes associated with effeminacy, and so ponce became somewhat associated with homosexuality.
An apparently unrelated slang usage of ‘ponce’ is to borrow or beg items, such as cigarettes, food or drinks; a ‘ponce’ in this context is someone who never pays their way.
Am I the only one who caught it’s use in Avengers: Age of Ultron?
Steve, ‘I’m only going to say this once.’
Tony, ‘How about nonce?’
I’m going to have to watch that again. Without intonation, I don’t know if maybe he was using nonce to mean not even once. As in: “I really don’t want to hear it.”
in the movie was that pronounced like “nunce” rhymes with “dunce” or like “nons” as like the front half of “nonsense”.
if like “nunce”, then they created a nonce word spelled “nunce” to rhyme with once. Which is a great use of nonce and nunce all at once. 
Yeah, they rhymed it with once, and I took it to mean ‘not even once.’
Not a word in my active vocabulary, but familiar with the encryption and temporal meanings, and just recently learned that embiggen is a perfectly cromulent “nonce word”.
School in Aus in the 70s. Never heard of the insulting meaning before now.
Old/apocryphal legal joke:
A newly appointed magistrate in the Orient has convicted a defendant of pimping but can’t remember what the appropriate sentence is. He sends a message to the outgoing magistrate asking “How much do you give a ponce?”. The reply comes back by very fast rickshaw “Never more than a shilling a bottle, m’boy!”
Care to explain that joke to a confused 'Murrican? What does “bottle” stand for or do in that joke?
The pounce/pimp has been convicted for living off immoral earnings, in this case selling illicit liquor/ sly grog. And his client list includes the previous magistrate.
Thank you. Utterly impenetrable to me.
Around here pimps sell sex, not booze.
for the purpose of Discourse