No imperfections. No wear and tear. All original, no repairs or changes. Slight pick scratches that can be wiped off may still constitute a mint rating.
Excellent
Only the slightest wear. Minor cosmetic repairs or mods. 100% playable condition.
Good
Cosmetic damage and/or imperfections and wear and tear but plays and functions well. Your basic player.
Fair
Above normal wear and tear for the items' age. Cosmetic damage or imperfections may be present. May have multiple major repairs and changes from original condition. You won't find guitars like this for sale here.
Poor
Less than fair condition. May have missing parts, major structural and cosmetic damage, wear and tear and/or imperfections. The item may not be playable or repairable. You won't find guitars like this for sale here.