"Unread books" refers to books that have not been read yet.
Sentences with «unread books»
Mt TBR is Goodreads shorthand for the mountain of unread books many of us own (To Be Read). (iolagoulton.com)
It could be a lul just due to having a large back log of unread books in your e-reader. (goodereader.com)
You can open the book you're currently reading or any recently read books, or browse for unread books in the file system or in any of seven bundled online catalogs — or you can add your own. (computerworld.com)