That's a good and practical option. Although, it can be a source of problems for genealogists. I have learnt a lot in this thread, especially that instead of saying 'a diacritic mark' I can say 'an accent mark'.(You could avoid the whole issue in Anglo-Saxon countries by merely spelling it bee-ah(r)-zed-oh-zed-kay-ay, Wolf)
The signwriter really doesn't know about accents because he should have put the rising accent mark on top of letter e.I would have thought, if someone doesn't know what an acute is, by that name, they have very little idea about accents anyway so you shouldn't tell them about it at all - like the signwriter on a pub near me that clearly advertises canápes. To have a chance of getting it right, they have to understand what an o-acute is.
If I still remember the word "acute", I will use it first. The longer expression contains more familiar words. In the case of Polish "ó" or English "é" it is better to use the word "line" than "dash". A dash is a short, horizontal line. I've learned that it separates parts of a sentence and functions like a colon.Those who don't know anything about accents might also have problems with the look of "a short rising line".
To go the whole hog, how about "oh with a short line sloping upwards on top of it"? (It will then be time to check out of the hotel). On the other hand, if your interlocutor is familiar with accents they might be offended. In other words it's best to try "acute accent" first.
For the "ł" I would say "el with a slash through it" (I don't think you need "upward sloping slash").
Yes, in everyday speech, "accent" is often used to refer to any diacritic (except by people who talk about a 'squiggle' or a 'blob' or a 'funny little thing' ).[...] I have learnt a lot in this thread, especially that instead of saying 'a diacritic mark' I can say 'an accent mark'.
Most Americans have been taught the traditional American symbol for the diphthong /oʊ/, which is ō (o with a macron, or "long sign"). I suspect that many Americans who heard "o with a dash" would think of ō.