It was an unused word that meant Book protector.
I had one of leather that had an inside divider meant for notes, a pen and book markers.
The word had other definitions also, such as: Book table, comfort clothes used when reading, reading lamp and a small knife such as a letter opener used in the past for recutting pages apart.
In French there was no word for ebook reader. The term used was 'lecteur électronique' (electronic reader) which was too generic and could mean too many things. I was against using 'liseuse' because it implied an other meaning for an already overused word. But after thought, maybe this word being used for this new application will open up French culture to ebooks, something that was long overdue. After all the French are noted for delaying novelty that does not come from them, this word might do the trick.