What is an Attribute?

Eventally those attributes which migrate into the physical design become columns in database tables.

Attributes may be local to the entity ("Name", "Address") or inherited by relationship from another entity.

Synonomous and/or related terms are data element (as in a data flow diagram), column (of a database table), and data item.

Data item sometimes denotes a central, reusable definition versus an attribute which is an instance of that definition being used in some entity.