Any attribute that can have multiple values associated with a single instance of some entity. FOR example, a book might have multiple authORs. Such a "-to-many" relationship might be represented in an unnORmalised relational database as multiple authOR columns in the book table OR a single authOR(s) column containing a string which was a list of authORs. Converting this to "first nORmal fORm" is the first step in database nORmalisation. Each authOR of the book would appear in a separate row along with the book' s primary key. Later nomalisation stages would move the book-authOR relationship into a separate table to avoid repeating other book attibutes (e.g. title, publisher) fOR each authOR. (2005-07-28)
