Nonce first appeared in Middle English as a noun spelled “nanes.” The spelling likely came about from a misdivision of the phrase “then anes.” (“Then” was the Middle English equivalent of “the” and anes meant “one purpose.”) The word was especially used in the phrase for the nonce, meaning “for the one purpose,”
There’s another folk etymology of this word, which leads brits like myself to laugh every time we read anything about cryptography… you can look it up in the urban dictionary…
It isn’t a folk etymology, it’s a homonym. Wiktionary has its etymology:
(1975) Unknown, derived from British criminal slang. Several origins have been proposed; possibly derived from dialectal nonce, nonse (“stupid, worthless individual”) (but this cannot be shown to predate nonce “child-molester” and is likely a toned-down usage of the same insult), or Nance, nance (“effeminate man, homosexual”), from nancy or nancyboy. The rhyme with ponce has also been noted.
However, the slang meaning has a folk etymology, as many slang words do:
As prison slang also said to be an acronym for “Not On Normal Communal Exercise” (Stevens 2012), but this is likely a backronym.
At university, we were also taught that nonce means “number used once”. Wikipedia seems to agree with you though:
Nonce is a word dating back to Middle English for something only used once or temporarily (often with the construction “for the nonce”). It descends from the construction “then anes” (“the one [purpose]”).[3] A false etymology claiming it to mean “number used once” is incorrect.[4] In Britain the term may be avoided as “nonce” in modern British English means a paedophile.[3][5]
Actually, no. nonce is a perfectly cromulent English word; the Oxford Dictionary defines it as
“Number used once” smells like folk etymology.
Merriam-Webster has the following etymolgy
https://www.merriam-webster.com/dictionary/nonce
That saif it is possible that nonce also have a separate technical definition in an RFC or similar document
There’s another folk etymology of this word, which leads brits like myself to laugh every time we read anything about cryptography… you can look it up in the urban dictionary…
It isn’t a folk etymology, it’s a homonym. Wiktionary has its etymology:
However, the slang meaning has a folk etymology, as many slang words do:
Ah interesting, thanks for the clarification! A lot of slang words are like this I suppose, unknown true origins but a few theories.
Another great place to find out more is Green’s dictionary of slang which (like the OED) is based on exemplar quotations.
At university, we were also taught that nonce means “number used once”. Wikipedia seems to agree with you though:
It appears to be cryptography 101 due to the wordy introductory first 2/3, but skip down to ‘The Bug’.