Sub-5 means: You would never have sex in public with a member of the other sex group. It is based upon an innovative recalibration the traditional 0-10 scale. 5 represents the point at which you can have sex only with one person and not be passionate about it. Ratings above 5 indicate how much you desire to have bone and ratings below 5 mean that you would avoid having it. A male alternative definition for a rating 5 is to describe someone you wouldn’t push into or attempt to take from your penis. Anonyms recognized: Supra-5, Super-5. (in Community Dictionary, added by Ildefonso Herrera)