Two from Casselman's "A companion to Macdonald's book on p-adic spherical functions":
The word ‘´epingler’ means ‘to pin’, and the image that comes to mind most appropriately is that of a mounted butterfly specimen. [Kottwitz:1984] uses ‘splitting’ for what most call ‘´epinglage’, but this is not compatible with the common use of ‘deploiement’, the usual French term for ‘splitting’.) Ian Macdonald, among others, has suggested that retaining the French word ´epinglage in these notes is a mistake, and that it should be replaced by the usual translation ‘pinning.’ This criticism is quite reasonable, but I rejected it as leading to noncolloquial English. The words ‘pinning’ as noun and ‘pinned’ as adjective are commonly used only to refer to an item of clothing worn by infants, and it just didn’t sound right.]
These phenomena are part of what Langlands calls endoscopy, a word that might be roughly justified by saying that endoscopy is concerned with some fine aspects of the structure of harmonic analysis on a reductive p-adic group. Langlands attributes the term to Avner Ash, praising his classical knowledge, but I was pleased to find recently the following quotation that shows a more vulgar intrusion of endoscopy into the modern world:
Jeeves: “ . . . I had no need of the endoscope.”
Bertie: “The what?”
Jeeves: “Endoscope, sir. An instrument which enables one to peer into the . . . interior and discern the core.”
From Chapter 12 of Jeeves and the feudal spirit by P. G. Wodehouse.
This discussion is about distingishing fae jewlry from real. Since the endoscope also has medical uses, one could imagine an even more vulgar usage.]usage.
He has modified the notes several times so these might not be there anymore, but I have the older copies =)