I am a New Zealander, and a common difficulty with visitors is the difference between “can’t” and “cunt”. The vowel has exactly the same sound, but it is long for can’t, and short for cunt. Can uses a different vowel sound from can’t, which means we can misunderstand Americans who don’t pronounce the t in can’t properly. Fortunately we can usually pick that a tourist using the word cunt usually means can’t. It is especially difficult for some people, because they don’t naturally understand vowel length changes. In Māori and Latin vowel length is critical to differentiate words.

Kiwis often understand both British and American usages of words, for example calling something “completely pants” makes sense to me. Pissed can be used in either a British or American sense.

I have only ever heard of nonce in the software engineering sense, and never in the perverse sense (and I have a much wider vocabulary than most).

Pants here means trousers, following the American usage.

Usage of some individual Māori words within an otherwise English sentence is becoming more common here (cultural pride versus historical cringe), but I would expect most kiwis avoid using them if speaking to a tourist.

I have always found it a bit immature that English or American philosophers shy away from pronouncing the name of Immanuel Kant correctly.

That reminds me how (Immanuel) Kant is correctly pronounced like "cunt" (in German) but English speakers pronounce it like "can't".

Nonce more specifically means someone who preys on children versus (say) a rapist who merely preys on adults.

For the nonce means the same in British English, it's just not very common. He was just winding you up because it can be interpreted as for the kiddie fiddler. Think of Tommy: Fiddle about, https://genius.com/The-who-fiddle-about-lyrics

Where in the US do people say 'for the nonce'? Because it certainly isn't where I am.

Never heard for the nonce in America

It’s used in software for sequencing in protocols so stuff doesn’t get repeated

Also cryptography.

Sure, but there it's generally understood to mean "Number used Once".

Huh? I immediately assumed the use in cryptography was related to... the normal use. Compare https://www.etymonline.com/word/nonce-word :

> "word coined for a special occasion," and not likely to be wanted again, 1884, from nonce "for a particular purpose" + word (n.).

And despite what you say, I still feel certain that's what's going on. The meaning is identical.

Sure but I thought above comment meant sequencing in genetic sense so it bore clarifying

It’s not a common part of most people’s vocabulary but not unknown among those with a higher rate of reading.

Yeah just to be clear, it’s not just a sex criminal but specifically a paedophile.

Anyone British working with cryptography should know it’s a number only once but, well, it can be awkward.

A few other bear traps: stuffed, knock up, napkin.