Weekends? Weekends are... the ... ends of the week. When you build a bookshelf, do you do:

<stack of bricks> <book> <book> <book> <book> <book> <stack of bricks>

or do you do:

<book> <book> <book> <book> <book> <stack of bricks> <stack of bricks>

When you want to know how your friend spent the previous Saturday and Sunday, do you ask:

"How was your weekend?"

Or do you ask:

"How were your weekends?"

When you purchase bookends, you get two, one for each end of the bookshelf.

A week is not a bookshelf, it's a snake. Does a snake have one end, or does it have two? Does a dog have two tails and two butts?

Weeks are not snakes, either. They're continuous, forever. Do snakes line up mouth to tail forever?

When they're stressed or ill, yes:

- https://www.iflscience.com/stressed-out-snake-eats-itself-24...

- https://en.wikipedia.org/wiki/Ouroboros

A week is not a snake. Each week is discrete and a different week from every other week.

Both ends of the week are the weekend.

One is the starting weekend, and the other the ending weekend.

Right, I (in the US) always figured "end" in the word "weekend" was akin to the two ends of a line segment, the two ends of a bar, etc.

To instead think of "end" in the word "weekend" as the opposite of "start" is to use a completely different definition of the word "end".

I wonder if "weekend" therefore has two definitions, given the split dependency.

It feels to me that for "end" to be used as the two ends of the week, it would be weekends (plural), not weekend (singular).

Considering that the word is from the British and the fact that the week ends with Sunday there, that can't be it. It would also be weekends, not weekend if there was multiple ends. The upcoming weekends doesn't mean Saturday and Sunday in the US... It occurs over a time period of at least one whole week into the future...right?

Sunday being the first day of the week came long (as in thousands of years) before the weekend was invented (which is a very recent development).

The same way all the other illogical things happened: random cultural legacy.

Why would you expect the week start day to be any different?

Because the week has two endpoints: the initial day of the week and the final day of the week.