'<term>' is always <my definition>; doesn't matter <other factor>.

Is never going to be true in spoken language. Otherwise we wouldn't be having conversations about confusion and ambiguity in the first place.

By my intuition, I'd say the uses of 'this week' and friends I described as improper qualify handily, not being all that widespread yet. A couple more marginal examples that stand out to me because erroneous uses are much more common: 'let alone' (which is binary and often used with subject and object reversed), the distinction between envy and jealousy.

You can take up a radical descriptivist position, e.g., that anything spoken by adult native speakers of normal faculties is never erroneous, or re-scope my assertions by saying that I'm gatekeeping speakers who see such usage as correct from my perceived language community or tradition, whatever, but imo the first is trivial and the second boring.

Sometimes specialists misappropriate methodological constraints from their discipline as general ontological or social principles, often discounting an inherent normativity in the way people actually relate to the things those specialists study. I think that's essentially at the heart of the most inflated and controversial uses of concepts like cultural relativism and linguistic descriptivism, and probably applies to nonspecific objections like the one you make above (as opposed to pointing at some specific dialectal variation in the use of such phrases or something like that).

Is it quirky that this expression doesn't instead mean 'the next Wednesday that will occur'? Yes, definitely. But I don't see how it's difficult to describe what it actually does mean.

That's the way it's supposed to be, at least as spoken in the part of Scotland from where my family hails.

But the Americans I know seem to get it wrong about half the time.

What I haven't figured out is if it's a regional (dialectical) thing, or just certain people being "dense", or simply never having been taught the rule.

> Sid: Well I'm going down to visit my sister in Virginia next Wednesday, for a week, so I can't park it.

> Jerry: This Wednesday?

> Sid: No, next Wednesday, week after this Wednesday.

> Jerry: But the Wednesday two days from now is the next Wednesday.

> Sid: If I meant this Wednesday, I would have said this Wednesday. It's the week after this Wednesday.

Well, usually. I've still had conversations like this:

Me: "It'll be next week on Wednesday."

Them: "Whoa, slow down there. Do you mean this coming Wednesday, or next week on Wednesday?"

Me: "It'll be next week on Wednesday."

Them: "Ohhhh! Thank you so much, it wasn't clear before."

If they name a rule after me, I want it to be, "If someone can reasonably interpret a phrase to mean two contradictory things, you have to stop using that phrase if you want clear communication, even if it means being more verbose."

Nope. This is highly contingent on "which day of the week starts a week" conventions.

If it is Sunday, then "next Wednesday" does not clearly mean the day 10 days from now ... and which one you lean toward will depend (in part) on "week starts on Monday" or "week starts on Sunday".

Things are also a bit complicated where I live by the fact that 'this weekend' and 'next weekend' follow the same pattern as I described before, but in a way consistent with calendar weeks beginning on Monday rather than Sunday— even though calendars here conventionally start the week on Sunday and usage of 'this <day of week>' and 'next <day of week>' align with that.

Anyhow, the variation you are getting at is already captured in the description I gave: as the calendar (week boundaries) varies, so does the description's meaning. The description is already indexed to a particular calendar (as is the expression, unfortunately implicitly). :p

My claim was that the meaning is easy enough to describe, not that the phrase is unambiguous. That a phrase can be used ambiguously doesn't mean that descriptions/definitions/characterizations of its general meaning actually have to be ambiguous or vague themselves.

Still yeah, this is a real problem for conversations between people who aren't looking at the same calendar/don't understand a shared convention for week boundaries.

My sense is that weekend nomenclature is even more confusing.

If it is Monday, and I say "next weekend", I'd wager there's a greater proportion of English speakers (at least) who would understand that to mean the two day period that starts in roughly another 4 days. That is: "next weekend" referred to at any time before (possibly) Friday means "the next one to occur", not "the one that is a part of the next calendar week". By contrast, on Friday "next weekend" pretty clearly means the two days that will occur in about 7 days, rather than "this weekend" meaning the two days that start in less than 24 hours.

> If it is Monday, and I say "next weekend", I'd wager there's a greater proportion of English speakers (at least) who would understand that to mean the two day period that starts in roughly another 4 days.

To my ear, this is wrong, but I think you're right that it's more common. I think 'this weekend' and 'next weekend' are fuzzier than 'this Tuesday' and 'next Tuesday' because of that misalignment I pointed to before, where 'the weekend' is thought of as a thing that comes at the end of a week, but how we write it most calendars where I live is as a thing that bookends the week on each side.

But I couldn't take up the usage you describe even if I moved to a region where it was predominant, I think. How could I abide a situation where 'this Saturday' occurs during 'next weekend'? That's simply madness. :D

(It's amazing how much we humans manage to communicate with something as messy as natural language-- perhaps especially amazing to programmer-brained people like me, who take some comfort and ease from the simplicity and neatness of the artificial formalisms we work with every day.)

for weekends, most of the time most people are talking in ways that make "this weekend" "the next weekend to occur". so here, "this" and "next" are effectively synonymous.

for days of the week, however, it is more often important to differentiate "this Thursday" (occuring in a couple of days from now, during this week) and "next thursday" (occuring in more than 7 days from now, as part of next week).

If my hunch is correct, it would make conventions highly dependent on social scheduling frequency in a culture.