Degree of Relationship

three degrees are
1>unary
2>binary
3>ternary

It basically represent the number of entities participating in relation.

Degree of relationship is the cardinality of relationship that defines the number of instances of one entity as it relates to the number of instances of the other entity.Depending on the combinations between two entities we can have either one-to-one, one-to-many or many-to-many relationship.
We have unary ,binary and ternary degrees of relationships.

The number of entity type involved
i.e
One : Unary
Two : Binary
Three : Ternary