What does "halfway across the room" mean?

Question

In the dictionary

Across: from one side to the other side of something

Side: [countable, usually singular] either of the two halves of a surface, an object or an area that is divided by an imaginary central line

Have a look at this paragraph from a story written by a native English speaker.

Ben was about to respond when suddenly his stool flew out from under him and across the room. Ben looked at his stool in surprise. It was halfway across the room.

Based on the 2 definitions above, this is what I think as shown in the below picture. The room is divided by an imaginary central line. Ben is on 1 side of the room. Then his stool under him flies to the other side of the room.

But I don't understand "halfway across the room"

And these are the pictures from the story

What does "halfway across the room" mean?

Answer 1

It is an idiomatic expression which is never normally used with any degree of precision - but merely to indicate that something happened further away than might be imagined, or to stress distance.

For example, I might say "Don't whisper to me from half-way across the room", even if the whisperer were only three feet away.

In other words it is never something to be taken absolutely literally - unless the speaker so indicates.

Answer 2

I (native AmE speaker) would understand it to mean "about as far away from Ben as it is from the other end of the room."

Across can also have the following meaning, according to Merriam Webster:

from one side to the opposite side of, over, through. "swam across the river"

"Across the room" would be on the opposite side of the room, so "halfway across the room" would be half of the way "across," or about at the "dividing line" in your image. Notice that this usage is not very precise. The object doesn't have to be exactly in the middle of anything; it just means that it's generally far away relative to the size of the room, but not as far as it could be.