>Now maybe they did spend some time learning it and looking into, but there is no way to know for sure

Why are you so concerned on this ? Isn't the goal of a paper is to communicate information?

>It only proves that they have copy and paste.

Yes they copy paste but it doesn't prove that they don't really understand it.

They may very well found your definition is the best way to describe it.

As long as the reader of the paper understand what being communicated, imo it should be fine?

I can understand if its a school assignment where the goal is specifically to prove that the author know their stuff.

For a scientific paper, requiring a concept to be described in different way for the sake of it seem to be inefficient and wasting time.