I use this grading system to describe all my hardcover books available in my eBay store 

Very Fine (VF).  Without faults or defects, in the same condition as when it was published. (Note: very few new books qualify for this grade, as there will often be rubs/scuffs to the dust-jacket from shipping, or bumped lower spine ends/corners from shelving.)

Fine (F).  Approaches the above, but not crisp. May show signs of having been carefully read, but no real defects or flaws.

Near Fine (NF).  Approaching Fine but with a couple of defects which should be noted

Very Good.  Used book showing some small signs of wear on either the binding or dust-jacket. Defects and faults should be noted

Good.  Average used book that has all pages present. All defects must be noted

Fair.  Used book that has complete text but may be missing end papers, half-title page, etc.  Dust-jacket may have noticeable signs of wear such as crimping, small tears, or curling on the edges. All defects should be noted

Poor/Reading Copy.  Sufficiently worn that its only merit is that it has the complete text. May be soiled, scuffed, stained or spotted and may have loose joints, hinges, pages, etc.  All defects should be noted

Ex-Library.  Must always be noted regardless of books condition

Book Club (BCE).  Must always be noted regardless of the books condition

Binding Copy.  A book in which the text block is complete but the binding is lacking or in such poor condition that it is beyond reasonable repair

Remainder Marks, Bookplates, Previous Owner's Name.  Should always be noted