What should be the term, "insert" or "insert size"?

Question

[Anisur Rahman]

First, I apologize for asking the same type of question again.

But, I think you will agree that there is a lot of inconsistent use of terminologies in the Bioinformatics discipline. And, that creates a hell of confusion sometimes.

We already know the concept of "insert size" as summarized in the following figure:

For my particular case, using the correct term is very crucial. That's why I am asking the question.
What does the word "insert size" mean for the DNA fragment between adaptors, adjective or noun? I mean, what does this word explain, the length property of the DNA fragment between adapters, or the name of it?

In a broad sense, this may not be a matter. But, this concept is at the core of my study. So, I have to use the term consistently.
I found that using the term "insert size" as a noun sometimes sounds weird, at least for people of non-Bioinfo discipline.

What should be the name of the "DNA fragment between adaptors"??
"Insert" or "Insert Size"???

I'd really appreciate your opinion.
Thank you.

Answer 1

[Mensur Dlakic]

I think this should be a matter of common sense. Let's not overthink it.

Insert is something that is embedded between points in space, and insert size is the property of that insert. The insert above is labeled by a colored rectangle in the upper right corner, so the insert size is used to make a point that its size is (fragment size - (adapter 1 length + adapter 2 length)).

[Anisur Rahman]

I also thought so.
But, the term insert size is so ubiquitously used in this field, that I just wanted to double-check. Thank you very much for your reply.

[Mensur Dlakic]

But, the term insert size is so ubiquitously used in this field, that I just wanted to double-check.

With a caveat that I am not in this field of research: my common sense tells me this is not possible. Insert and insert size are not interchangeable terms. Maybe many people decided to make confusing figures such as the one you have shown, but even in that figure the insert is labeled clearly by a green-blue rectangle. The blue line, especially with arrows at both ends, is meant to specifically draw attention to its size.

[kalavattam]

I agree—I haven't really seen 'insert' and 'insert size' used interchangeably. However, I have noticed that 'insert' and 'fragment' (or 'insert size' and 'fragment size') are sometimes used synonymously, despite differences in their meanings.

[Mensur Dlakic]

I have seen this as well, and maybe there is some justification for it. When adapters are a good deal smaller than the insert (I think that happens most of the time), insert size and fragment size are going to be in the same ballpark.

[Anisur Rahman]

Maybe I misunderstood.
By the way, it more clear to me now. Thank you.