DJ : Short for dust jacket, a protective and often decorative wrapper, usually made of paper which wraps around the binding of a book.

jacket : Sometimes used as another term for dust jacket, a protective and often decorative wrapper, usually made of paper which wraps around the binding of a book

vg : Very Good condition. can describe a used book that does show some small signs of wear - but no tears - on either binding or paper. Any defects must be noted. (defined by AB Bookman's Weekly)