Is this definition of calendar year wrong?

[Acsenray]

@UDS

Well, as has been pointed out earlier in this thread, descriptive dictionaries confirm that the term is used in both senses. And that conforms to my own experience. It may not conform to you experience, but why should your experience be normative?

Because you’re talking to me in this thread.

Plus, I have to note that you qualify your own arguments by reference to context. You point out that the term has the Jan/Dec sense “if we’re talking about taxes and the IRS”,

I didn’t say that. You’re thinking of someone else.

and you construct an argument on the basis that “there are no commonly used calendars that are ordinarily referred to for business purposes that start and end on any other days”.

You can’t discuss usage without discussing context. If you’re going to talk about what “calendar year” means you have to put it in the context of when it is likely to be used. I have never heard people say “calendar year” outside of a business context.

Leaving aside th fact that the second statement is false - calendars commencing on days other than 1 Jan are routinely used for business purposes -

Of course they are. And they are specified—fiscal year, for example. Which supports my point.

doesn’t the fact that you felt the need to qualify your case in this way indicate some awareness that , outside the tax/business context, the term is indeed used more flexibly?

You haven’t offered any common context in which it would be likely to use “calendar year” in that sense. Without context, your assertion is theoretical or highly specialized. And if that’s the case, then your assertion should be qualified with “In the highly specialized contexts in which I operate, it means this …”

[Inner_Stickler]

The OP doesn’t give a whole lot of context but the implication I got was that he ran into the unusual use of calendar year in a business context and between that and the M-W definition linked above, I think it’s safe to say that regardless of our personal feelings and intuition on the matter, people do use calendar year to mean a unit of time equal in length to the period measured by a calendar.