This question originates from
here, particularly at the #11th post.
The main reason I'm asking this is that I'd like to make use of such a feature for looking up dictionary definitions from an EPUB file. That seems to me the only solution for having an Italian dictionary - albeit illegally obtained - on e-reading devices that offer none.
I should also point you out that it would be helpful, if not necessary, to be able to search even through the tapping of a word. If that of directly opening the dictionary book, which I would gladly reject, isn't the only alternative, please illustrate how one can generally do searches through normal books on PocketBook devices.